Question

The total weight of Robbie and a trophy is 69.95 kg. The total weight of Sarah and the trophy is 63.1 kg. If Robbie and Sarah weigh 116.05 kg in all, find the weight of the trophy, Robbie, and Sarah?

Answer 1

Robbie ,sarah and the trophy weigh 61.12 kg, 54.93 kg and 8.38 kg respectively.

Explanation:

Let the weight of Robbie = x kgs

the weight of Sarah= y kgs

the weight of the trophy =z kgs

Then, from the given data in question a set of equations can be computed:

• the weight of robbie and trophy is 69.95 kgs , that is:

x+z=69.95 ......1

• the weight of Sarah and a trophy is 63.31 kilograms,

y+z=63.31 ------------------2

• the weight of Robbie and sarah is :

x+y=116.05 kg------------------3

Solving these equations:

x=69.5-z--------------------------4

then,putting this value in 3,

69.5-z+y=116.05

y-z=46.55----------5

adding equation 2 and 5

y+z+y-z=63.31+46.55

or, 2y=109.86

y=54.93 kgs

Also,

y-z=46.55

z=8.38 kgs

Again,

x=69.5-8.38

x=61.12 kgs