Question

A ribbon was cut into three pieces of lengths 12/5, 7/2, and 23/5. What fraction is: 1. the first piece of the whole ribbon? 2. the second and the third pieces together of the whole ribbon?

Answer 1

first part of the ribbon / sum of all the parts of the ribbon = [12/5]/[12/5+7/2+23/5] 
= [12/5]/[21/2] 
12/5 x 2/21 = 8/35
second part of the ribbon + third part / sum of all the parts of ribbon = [7/2+23/5]/[12/5+7/2+23/5] 
= 81/10 x 2/21 = 27/35

the first piece of ribbon is 8/35
the second+third piece of ribbon is  is 27/35 

thankyou

Answer 2

Lengths of 3 prices of ribbon are 12/5 , 7/2 and 23/5 .

So, length of whole ribbon =

12/5 + 7/2 + 23/5

= (24+35+46)/10

=105/10


Q.1) What fraction is first piece of whole ribbon.
S1) (12/5) / 105/10
= 12/5 × 10/105
= 4/1 × 2/35
= 8/35

A1) First piece is 4/35 fraction of whole ribbon.

Q2) What fraction is 2nd and 3rd pieces together of whole ribbon?
S2) Sum of 2nd and 3rd pieces
= 7/2 + 23/5
= (35+46)/10
=81/10

Therefore, the fraction which second and third ribbon together of whole ribbon is -

81/10 ÷ 105/10
= 81/10 × 10/105
= 81/105
=27/35

A2) 2nd and 3rd ribbon together are 27/35 fraction of whole ribbon.