Question

Mr lee owns a toy store. He orders 20 toys consisting of airplanes, cars, and trains. The number of airplanes is 2/3 the number of cars. The number of cars is 3/5 the number of trains. The price of each toy airplane is $12 and the price of each toy car is $8. Each toy train costs 1/2 as much as the toy airplane. How many toy cars does he buy? How much does Mr lee spend for the toys?

Answer 1

Toy Cars=6 and total spending by Mr.Lee=$156

Explanation:

Let us first consider

Number of Airplanes=A Cars=C and Trains=T

Now how to start with the problem ? Just start reading it step by step. First statements says that The number of airplanes is 2/3 of The number of cars.

Now how to convert it into an mathematical expression?

here the word "=" is of most important, The number of airplanes "is" whenever you encountered "is" just place a "="

so the first statement can be converted into mathematical expression as,

A=2/3*C (The number of airplanes is 2/3 of The number of cars.)

Now as per the second condition we can write it in mathematical form as,

C=3/5*T (The number of cars is 3/5 the number of trains).

and the third condition as,

C=3/5*T (The number of cars is 3/5 the number of trains).

Now , we have expressed the statements in mathematical expressions. we have three expressions.

Now It is also given that total number of Toys=20 so we can write it as,

A+C+T=20. ............(1)

Till now we have expressed everything in the question in mathematical form.

now for solving such type of question we need to express the expression giving total in a single entity, expressed it in terms of Airplanes,Cars or Trains,

here we are expressing it in terms of Cars so we can rewrite it (1) as,

2/3*C+C+5/3*C=20 (A=2/3*C and C=3/5*T so T=5/3*C)

by solving this we will get C=6

Total number of car toys, answer of first part

now put this value of C in expression 1,

2/3*C+C+T=20

so the value of T will be 10. T=10

and the total is toys are 20 so 20-10+6=4

Means Airplanes are 4.

Now the cost for each toy is.

A=$12,C=$8 and T=1/2 A i.e T=$6.

So the total cost would be,

4*12+6*8+10*6=$156

$156 answer of second part

I Hope this will help you to solve such kind of Problems.