For every $5 I earn from my job, I save $2. For every $4 I save from my job, I am given an additional $1 from my parents to add to my saving. How much must I earn in order to have $40 in savings?

APatel Jan 10, 2019

#1**+1 **

x = # $5 unit you earn

2x = amount you save per unit

2x/4 = amount from parents

2x + 2x/4 = 40

10x/4 = 40

10x=160

x = 16 $5 units = $80 (oops....corrected 16 x5 = 80 not 75 as I originally posted)

ElectricPavlov Jan 10, 2019

edited by
ElectricPavlov
Jan 10, 2019

edited by ElectricPavlov Jan 10, 2019

edited by ElectricPavlov Jan 10, 2019

edited by ElectricPavlov Jan 10, 2019

edited by ElectricPavlov Jan 10, 2019

#2**+1 **

We have this equation

( [ E / 5 ] *2 ) + [ ( [ E / 5 ] ) * 2 ] / 4 = 40 where E is the amount you earn

Simplify

(2/5)E + (1/10)E = 40

(4/10)E + (1/10)E = 40

(5/10)E = 40

(1/2)E = 40 multiply by 2

E = 80

Check

For $80 you will save (80 / 5) * 2 = 16 * 2 = $32

And your parents give you 32/4 = $8 more

CPhill Jan 10, 2019