#### Doubling ages

Today Julia is 16 years older than Laura. If in 4 years Julia will be twice as old as Laura, how old will Julia and Laura be now?

# Linear equations

Modeling
8

#### Equation application. Modeling

A clothing piece has a rectangle form (as in the image); we know that its width is 12 cm less than its length. If the semi perimeter of this rectangle is 34 cm, find the length and the width of this rectangle form clothing.

# Linear equations

Modeling
10

#### Linear equation transformation 2

Approximate the following equation: $14x - 5 - 3x + 4 - 2x + 9 = 12 - 4x + 7 + 6x - 3$

# Linear equations

Training
7

#### The water tank

In a house, the water deposit is at 2/7 its capacity. Three people have showers: The first one uses one fifth of the quantity in the tank; the second uses a third of what's in the tank and the third, three fourths of the firsts' quantity. Which is the capacity of the tank and how much water did the first two use is we know that the third used 10 litres to shower?
# Monomials & polynomials
# Units & rounding

Training
8

#### Guess the unknown number

Given a number, adding half of it, double it and triple it is 55. What number is it?

# Linear functions

Training
5

#### John's journey to school

John travels every day a 1 km long road at 6km/h to go to school. How long will it take John to get to his destination?

# Linear functions

Training
5