Question

A) Pedro tiene 14 años y su hermana Elisa tiene 3. ¿Cuántos años tienen que pasar para que la edad de Pedro sea el doble de la de su hermana?

La suma de tres números consecutivos es igual a uno más que el doble del mayor.Halla esos tres números.

Answer 1

a. 8

b. 2, 3, 4

Explanation:

We have to:

Pedro's age = 14 years

Elisa's age = 3 years

The years to elapse = x

Pedro's age = 14 + x

Elisa's age = 3 + x

14 + x = 2 * (3 + x)

14 + x = 6 + 2 * x

14 - 6 = 2 * x - x

x = 8

Eight years must pass before Pedro's age is twice Elisa's

Now the second question:

Let x be the smallest number

Let x + 1 be the consecutive number

Let x + 2 be the consecutive number

x + (x + 1) + (x + 2) = 2 * (x + 2) +1

x + x +1 + x + 2 = 2 * x + 4 + 1

3 * x +3 = 2 * x + 5

3 * x -2 * x = 5 - 3

x = 2

So:

x = 2

x + 1 = 2 + 1 = 3

x + 2 = 2 + 2 = 4

Therefore the numbers are 2, 3, 4 are consecutive and equality is true