Question

The ratio of Mary's mass to Peter's mass is 5:7. Norman's mass is 13 kg more than Mary's mass but 9kg less than Peter's mass. Find the mass of Mary.​

Answer 1

Answer:

If the ratio of Mary's mass to Peter's mass is 5:7 and Norman's mass is 13 kg more than Mary's mass but 9 kg less than Peter's mass, then mass of Mary is 55 kg.

Step-by-step explanation:

Given

Ratio of Mary's mass to Peter's mass = 5:7

That is if Mary's mass is 5x ,then Peter's mass is 7x

Given

Norman's mass is 13 kg more than Mary's mass but 9 kg less than Peter's mass

Let Y be Norman's mass

Then Y = 5x+13

And Y = 7x- 9

Therefore, 5x+13= 7x-9

7x-5x=13+9

2x= 22

x= 22/2

= 11

Therefore x= 11

Mass of Mary = 5x

= 5*11

=55kg

So, the mass of Mary is 55 kg