Question: Leila bought a living room set consisting of a sofa worth $1,250, 2 armchairs costing $425 each and a coffee table. The total amount of the invoice is $2,430. What is the price of the coffee table?
Answer with step-by-step thinking: The price of 2 armchairs is $425 x 2 = $850. Mrs. Dubois will pay $850 for the 2 seats. Thus the Coffee table price is $2,430 – ($1,250 + $850) = $2,430 – $2,100 = $330.
So the answer is 330.


Question: Sally bought 3 photograph frames, each costing her $3. She paid with a $20 bill. How much change did she get?
Answer with step-by-step thinking: She bought the frames for 3 × $3 = $9. Sally got $20 - $9 = $11 in change.
So the answer is 11.


Question: The ratio of boys to girls in a family is 5:7. The total number of children in the family is 180. If the boys are given $3900 to share, how much money does each boy receive?
Answer with step-by-step thinking:
The total ratio representing the number of children in the family is 5 + 7 = 12. From the total ratio of children in the family, 5 / 12 represent the number of boys, meaning that the number of boys in the family is 5 / 12 * 180 = 75. If the boys are given $3900 to share, each boy receives $3900 / 75 = $52.
So the answer is 52.