Question

Farmer martin is trying to reduce the number of birds in his field. On the first day, he counts 575 birds. On the second day, he adds a scarecrow and reduces the number of birds in his field by one fifth, on the third day he adds a second scarecrow, and counts only 345 birds. If the pattern continues, how many scarecrows will he need to get below 100 birds?? Explain how you got your answer PLZ help

Answer 1

One fifth of 575 birds is 115 birds, therefore the total decreases to 460. A second scarecrow decreases it to 345 birds, which is a decease in 115 again. Therefore the expression is y = 575 - 115x, and to get number of scarecrows below 100, you will need 5 scarecrows.