Steve has 50 notebooks with red covers but only 40 notebooks with blue covers. If he uses up 6 notebooks with red covers and 4 with blue covers each month, in how many months will he have the same number of red as blue notebooks?

5 months

Step-by-step explanation:

The first thing to do is to obtain the difference between the two numbers of colored books, 50 and 40.

50 - 40 = 10 notebooks.

We need to calculate how long it will take for this difference to disappear, noting that Steve uses more of the red cover notebooks every month. The difference on a monthly basis is

6 - 4 = 2 notebooks per month

So, now the number of months will be gotten from;

Number of months =

Number of months = = 5 months

We can check for this,

After 5 months, Steve would have used 5 × 6 red cover notebooks = 30

and 5 × 4 blue cover notebooks = 20

The remaining number of books will be:

RED: 50 - 30 = 20 red cover notebooks

BLUE: 40 - 20 = 20 blue cover notebooks.