steven sells cardboard. he sold 350 units in march, 50 more units in april than is march and 350 more units in may than in april. the average number of units sold per month over this period was?

500

Step-by-step explanation:

Let's see how many cardboards he sold in each month:

March: 350 units

April 350 + 50 = 400 units

May: 400 + 350 = 750 units

The average is the total of units he sold in the period we are considering, divided by the amount of months of that period.

Total: 350 + 400 + 750 = 1500

Amount of months = 3 (March, April and May)

So, the average is 1500/3 = 500