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Exercises: Problems with equations

Practice★☆☆
In an eSports tournament, Alex's team has scored three times as many points as Lucy's team. If between the two teams they have scored a total of $152$ points, how many…

In an eSports tournament, Alex's team has scored three times as many points as Lucy's team. If between the two teams they have scored a total of $152$ points, how many points has each team obtained?

Solve
Practice★☆☆
Emma is $4$ years older than her little brother, Ethan. In $6$ years' time, the sum of their ages will be $32$ years. Calculate the current age of each one by setting up…

Emma is $4$ years older than her little brother, Ethan. In $6$ years' time, the sum of their ages will be $32$ years. Calculate the current age of each one by setting up a linear equation.

Solve
Practice★☆☆
A rectangular school vegetable garden is to be fenced to protect the crops. We know that the length of the garden measures $5$ feet more than the width and that $38$…

A rectangular school vegetable garden is to be fenced to protect the crops. We know that the length of the garden measures $5$ feet more than the width and that $38$ feet of fencing were needed to completely surround it. What are the dimensions of the garden?

x x + 5 Total perimeter P = 38 ft
Solve
Practice★☆☆
A group of friends buys tickets for a concert. The "standing" tickets cost $\$15$ more than the "seated" ones. If they buy one of each type and the total bill is $\$85$,…

A group of friends buys tickets for a concert. The "standing" tickets cost $\$15$ more than the "seated" ones. If they buy one of each type and the total bill is $\$85$, what is the price of each ticket?

Solve
Practice★☆☆
The sum of three race bib numbers, which happen to be three consecutive integers, is equal to $63$. What numbers are these three runners wearing on their shirts?

The sum of three race bib numbers, which happen to be three consecutive integers, is equal to $63$. What numbers are these three runners wearing on their shirts?

Solve
Practice★☆☆
A food delivery app rider is carrying twice as many pizzas as burgers in their backpack. If they are transporting a total of $12$ orders between pizzas and burgers, how…

A food delivery app rider is carrying twice as many pizzas as burgers in their backpack. If they are transporting a total of $12$ orders between pizzas and burgers, how many of each kind are there?

Solve
Practice★☆☆
Lucy has started saving to buy a tablet that costs $\$240$. She has already saved $\$60$ and, from now on, she is going to put away $\$12…

Lucy has started saving to buy a tablet that costs $\$240$. She has already saved $\$60$ and, from now on, she is going to put away $\$12$ of her allowance every week. How many weeks will it take her to have enough money for the purchase?

Solve
Practice★☆☆
Calculate the side length of a square advertising panel knowing that if its side were to increase by $2$ feet, its area would increase by $16$ square feet.

Calculate the side length of a square advertising panel knowing that if its side were to increase by $2$ feet, its area would increase by $16$ square feet.

Original Area = x² Extra area + 16 ft² x 2 x 2 x + 2 x + 2
Solve
Practice★★☆
Find three consecutive integers such that the sum of the first two is equal to three times the third minus 14 units.

Find three consecutive integers such that the sum of the first two is equal to three times the third minus 14 units.

Solve
Practice★★☆
A new rectangular play area is being designed in a municipal park. It is known that the length of the area must be $5$ feet greater than the width. If the total area…

A new rectangular play area is being designed in a municipal park. It is known that the length of the area must be $5$ feet greater than the width. If the total area intended for the games is $150$ $m^2$, calculate the dimensions (length and width) that this area will have.

Area = 150 ft² x x + 5
Solve
Practice★★☆
Currently, a father's age is three times that of his daughter. In $12$ years' time, the father's age will only be double that of his daughter. How old is each of them…

Currently, a father's age is three times that of his daughter. In $12$ years' time, the father's age will only be double that of his daughter. How old is each of them currently?

Solve
Practice★★☆
Two cyclists, Lucy and Marcus, are at a distance of $60$ $km$ and decide to meet at an intermediate point. Lucy sets off from $A$ towards Marcus at a constant speed of…

Two cyclists, Lucy and Marcus, are at a distance of $60$ $km$ and decide to meet at an intermediate point. Lucy sets off from $A$ towards Marcus at a constant speed of $20$ $km/h$. At the same time, Marcus sets off from $B$ towards Lucy at a speed of $10$ $km/h$. How long will it take them to cross paths and at what distance from point $A$ will they meet?

v₁ = 20 mph v₂ = 10 mph A (Lucy) B (Marcus) Meeting 60 miles x 60 - x
Solve
Practice★★☆
In a gourmet shop, they want to mix two types of coffee. "Arabica" coffee is priced at $\$12$/lb and "Robusta" coffee costs $\$8$/lb. If we want to obtain a mixture of…

In a gourmet shop, they want to mix two types of coffee. "Arabica" coffee is priced at $\$12$/lb and "Robusta" coffee costs $\$8$/lb. If we want to obtain a mixture of $20$ $kg$ that works out at a price of $\$10,50$/lb, how many pounds of each type of coffee must we use?

Solve
Practice★★☆
Find a natural number such that the difference between its square and three times the number is equal to $40$. Is the solution to this problem unique in the set of…

Find a natural number such that the difference between its square and three times the number is equal to $40$. Is the solution to this problem unique in the set of natural numbers? Justify your answer by setting up the corresponding equation.

Solve
Practice★★☆
A group of friends wants to buy a birthday present that costs $\$120$. At first there were a certain number of people, but at the last minute $2…

A group of friends wants to buy a birthday present that costs $\$120$. At first there were a certain number of people, but at the last minute $2$ more friends joined in, which meant that everyone had to pay $\$5$ less. How many friends were there initially in the group?

Solve
Practice★★☆
Calculate the dimensions of an isosceles triangle knowing that the unequal side measures $4$ $cm$ less than each of the equal sides and that the total perimeter is $26$…

Calculate the dimensions of an isosceles triangle knowing that the unequal side measures $4$ $cm$ less than each of the equal sides and that the total perimeter is $26$ $cm$. Once the sides have been found, calculate the area of the triangle.

Perimeter = 26 in h x x x - 4
Solve
Practice★★★
A graphic designer is working on the logo for a new company. The design consists of a central rectangle for the name, surrounded by a decorative border of uniform…

A graphic designer is working on the logo for a new company. The design consists of a central rectangle for the name, surrounded by a decorative border of uniform thickness $x$. The inner rectangle has dimensions of $12\text{ cm}$ by $8\text{ cm}$. If the total area of the logo (including the border) must be exactly double the area of the inner rectangle, what must the thickness $x$ of this border be?

Aₜ = 2 · Aᵢ LOGO
Solve
Practice★★★
A mother's current age is the square of her daughter's age. In $9$ years' time, the mother's age will only be three times the age her daughter is at that time. Find the…

A mother's current age is the square of her daughter's age. In $9$ years' time, the mother's age will only be three times the age her daughter is at that time. Find the current ages of both.

Solve
Practice★★★
Two cities, $A$ and $B$, are separated by a distance of $155\text{ km}$. At 10:00, a cyclist leaves $A$ towards $E$ at a constant speed of $20\text{ km/h}$. An hour and…

Two cities, $A$ and $B$, are separated by a distance of $155\text{ km}$. At 10:00, a cyclist leaves $A$ towards $E$ at a constant speed of $20\text{ km/h}$. An hour and a half later, a motorcycle leaves $E$ towards $A$ at a speed of $80\text{ km/h}$. At what time will they cross paths and at what distance from city $A$ will they meet?

Meeting point A B
Solve
Practice★★★
In a chemical laboratory, $20\text{ liters}$ of an acid solution at $25\%$ are needed. The technician has two jugs available: one with a mixture at $10\%$ acid and…

In a chemical laboratory, $20\text{ liters}$ of an acid solution at $25\%$ are needed. The technician has two jugs available: one with a mixture at $10\%$ acid and another with a concentrated mixture at $50\%$. How many liters from each jug must be mixed to obtain the desired concentration?

Solve
Practice★★★
An investor has $12\,000\text{ \$}$ which they divide into two parts to deposit into two different financial products. The first offers an annual return of $4\%…

An investor has $12\,000\text{ \$}$ which they divide into two parts to deposit into two different financial products. The first offers an annual return of $4\%$, while the second, which is riskier, offers an annual return of $7\%$. If at the end of the year the total profits obtained were $630\text{ \$}$, what amount did they allocate to each product?

Solve
Practice★★★
The area of a right triangle is $30\text{ cm}^2$ and its hypotenuse measures $13\text{ cm}$. Calculate the length of the two shorter sides of the triangle.

The area of a right triangle is $30\text{ cm}^2$ and its hypotenuse measures $13\text{ cm}$. Calculate the length of the two shorter sides of the triangle.

a b 13 in Area = 30 in²
Solve
Practice★★★
Two pipes connected to a tank can fill it together in $4\text{ hours}$. If used separately, the pipe with the smaller diameter takes $6\text{ hours}$ longer than the…

Two pipes connected to a tank can fill it together in $4\text{ hours}$. If used separately, the pipe with the smaller diameter takes $6\text{ hours}$ longer than the pipe with the larger diameter to fill the entire tank. How long would each pipe take on its own?

Solve
Practice★★★
Find a two-digit number knowing that the sum of its digits is $12$ and that, if the order of its digits is reversed, the new number obtained exceeds the original by $18$…

Find a two-digit number knowing that the sum of its digits is $12$ and that, if the order of its digits is reversed, the new number obtained exceeds the original by $18$ units. Represent the original number as $10x + y$.

Solve