Question

A strings is divided into three sections. The first section is three-fourths the length of the third section. The second sectionis one-half the length of the third section. if the length of the string is 18cm, what is the length of the first section?

Answer 1

Let's name the third section x
The first section is then 3/4 x
And the second one is 1/2 x

Together they are 18 cm long

`x + (3)/(4) x + (1)/(2) x = 18`
Which means

`(9)/(4) x = 18`
And multiplied by 4 and devided by 9 this equals

`x = 8`
So we have the third section's lenght.
But they are asking for the first one's. The first section is 3/4x


`y = (3)/(4) x`

`y = (3)/(4) * 8`

`y = 6`
The lenght of the first section is 6cm