At a craft fair martin made $52.50 selling wooden keychains if he sold the keychains for $0.75 each how many keychains did he sell

In all, 70 keychains were sold at $0.75 each.

Step-by-step explanation:

This problem can be solved by forming an equation using the given values, cost for each keychain and total cost of selling all keychains, and the value to be found out, number of keychains sold.

We substitute a variable for the value to be found out.

The equation is then solved by transfer of values and/or variable on the opposite side of the equal sign.

When a value/ variable is transferred on the opposite side of the equal sign, the sign of the value/ variable becomes the opposite.

The negative sign becomes positive and multiplication becomes division, and vice-versa.

The equation will include all the three values - total cost of selling all keychains, cost of each keychain and the number of keychains.

The values from the problem and the substitute variable for the unknown value are explained below.

1. Let the number of keychains be n.

2. The cost of each keychain is $0.75.

3. The total cost of selling n number of keychains is $52.50.

Now, $52.50 is earned after selling n number of keychains at $0.75 for each keychain.

When we multiply, cost of each keychain and the number of keychains sold, we get the total cost.

By combining all the above values using mathematical operations, we get the following equation.

0.75 x n = 52.50

We transfer 0.75 on the other side of the equal sign.

On the left side, n is multiplied by 0.75, hence, on the other side of the equal sign, i.e., on the right side of the equal sign, 52.50 will be divided by 0.75.

=> n = \frac{52.50}{0.75}

We further solve the fraction on the right side of the equal sign.

We get the value on n as shown.

=> n = 70  

Hence, total number of keychains sold were 70.