Question

The number of bacteria in a petri dish is 524 and growing at a rate of 7% every month.

Answer 1

This is an exponential growth problem.
y = 524(1.07)^7
y = 841 bacteria after 7 months

Answer 2

Month 0 = 524
Month 1 = 524 + (524*.07) = 560.68
Month 2 = 560.68 +(560.68*.07) = 599.9276
Month 3 = 599.9276 +(599.9276*.07) = 641.922532
Month 4 = 641.922532 +( 641.922532*.07) = 686.8571092
Month 5 = 686.8571092 +(686.8571092*.07) = 734.9371068
Month 6 = 734.9371068 +(734.9371068*.07) = 786.3827043
Month 7 = 786.3827043 +(786.3827043*.07) = 841.4294936

Round to nearest whole number = 841 bacteria in the petri dish.