Because of the unexpected cold weather, the cost of tomatoes increased 50 percent in one month. if the cost after the increase was 60 cent per pond, what was the cost before the increase?

A 50% increase is just taking the original amount and adding half of that towards the amount.

Example : 50% of 100 is 50 so a 50% increase to 100 would be 150

a formula for this would be X + (1/2×X) = Y

in your case we're working backwards with the known being 60

We can just plug in reasonable values for X until we get 60

50% of 40 is 20

40 + 20 = 60

so the original amount was 40