Question

Evans uncle gave his money for his birthday. He puts half of the money in his savings account,spend 1/5 of the money on bubble gum to share with his friends,and buy comics with the rest. What portion of money will he spend on comic books?

Evans uses some of his comic book money to buy a magazine for $4. Evans uncle gave him $30, what fraction of the money did he spend on he magazine

Answer 1

Let

x-------> amount that Evans uncle gave for the birthday

Part a) What portion of money will he spend on comic books?

we know that

1) Evan puts half of the money in his savings account

so

`x-(x)/(2) =(x)/(2)`

the rest is equal to
`(x)/(2)`

2) Evan spend
`(1)/(5)` of the money on bubble gum to share with his friends

`(x)/(2) -(x)/(5) =((5x-2x))/(10) \\ \\ =(3)/(10)x`

the rest is equal to
`(3)/(10) x`

3) Evan buy comics with the rest

the rest is equal to
`(3)/(10) x`

therefore

the answer Part a) is

The portion of money that Evan will spend on comic books is
`(3)/(10)`

Part b) Evans uses some of his comic book money to buy a magazine for $4. Evans uncle gave him $30, what fraction of the money did he spend on he magazine

The portion of money that Evan will spend on comic books is
`(3)/(10)x`

`x=30`

So

`(3)/(10)*30=9`$

by using proportion

`(9)/(1) =(4)/(x) \\ \\ 9*x=4\\ \\ x=(4)/(9)`

therefore

If the question refers to the fraction with respect to the money used for the comics

then

the answer Part b1) is

`(4)/(9)`

If the question refers to the fraction with respect to the total money

then

by using proportion

`(30)/(1) =(4)/(x) \\ \\ 30*x=4\\ \\ x=(4)/(30)`

`(4)/(30) =(2)/(15)`

the answer Part b2) is

`(2)/(15)`

Answer 2

1/2 of the money put in savings and 1/5 of the money spent on bubble gum gives us:

1/2 + 1/5 = 5/10 + 2/10 = 7/10 of the money.

So he spent 3/10 of the moeny on comic books (because 1 - 7/10 = 3/10).

Now 3/10 of $30 is:

30 * 3/10 = 3 * 3/1 = 9

So Evan had $9 for comic books and he spent 4/9 of of his comic books money for the magazine.