Question

Mariam went to a shop and bought 8 snickers, 3 galaxy and 3 kitkat. She payed 8 BD

Answer 1

Answer:

Yes

Step-by-step explanation:

Let s be the price of snickers, g the price of galaxy and k the price of kitkat.

●For Mariam the equation will be:

8 s + 3 g + 3k = 8

●For Zainab the equation will be:

4 s + 9 g + 4 k = 10.9

Take the first equation and divide both sides by 4 to make it easier.

You get:

● 2s + 0.75 g + 0.75k = 2

Take the second equation and divide both sides by 2 to make easier.

You get:

● 2s + 4.5g + 2k = 5.45

The new system of equation is:

● 2s +0.75g + 0.75k = 2

● 2s + 4.5g + 2k = 5.45

Express s in the first equation using the other variables.

● 2s +0.75g +0.75k = 2

● 2s + 0.75(g+k) = 2

● 2s = 2-0.75(g+k)

● s = 1- 0.325 (g+k)

Replace s by the new expression in the second equation:

●2 [1-0.325(g+k)] +4.5 g +2k = 5.45

●2-0.75(g+k) +4.5g + 2k = 5.45

●2- 0.75g -0.75k +4.5 g +2k = 5.45

●2+ 3.75g + 1.25k = 5.45

● 3.75g +1.25k = 3.45

We have eliminated one variable (s)

We will keep (3.75g+1.25k=3.45) and use it.

Now that we eliminated in the second equation do it again in the first one.

You will get a system of equations with two variables.

Solve it and replace g and k with the solutions.

Finally solve the equation and find s.