## Please help!!!! I just need help with part c. A pumpkin is being grown for a contest at the state fair. Its growth can be modeled

Please help!!!! I just need help with part c.

A pumpkin is being grown for a contest at the state fair. Its growth can be modeled by the equation P=25(1.56)^n, where P is the weight of the pumpkin in pounds and n is the number of weeks the pumpkin has been growing.

a. By what percentage does the pumpkin grow every week?

(my answer) The pumpkin grows 156% percent every week.

b. After how many weeks will the pumpkin be 80 pounds?

(my answer)The pumpkin will be 80 pounds after 3 weeks.

c. What if the growth percentage changed to 32, after how many weeks will the pumpkin be 80 pounds?

## Answers ( No )

A) the growth is 56% per week. The 1.56 is multiplying the weight of the pumpkin now by the 56% to get the total weight after the 56% increase.

B) Replace P with 80 and solve for n:

80 = 25(1.56)^n

Divide each side by 25:

80/25 = 1.56^n / 25

3.2 = 1.56^n

Take the natural logarithm of both sides:

ln(3.2) = ln(1.56^n)

Remove the exponent:

ln(3.2) = n(ln(1.56)

Divide both sides by ln(1.56)

n = ln(3.2) / ln(1.56)

n = 2.6 weeks, round to 3 weeks.

C) Change 1.56 to 1.32 and redo the same calculation from B.

80 = 25(1.32)^n

80/25 = 1.32^n /25

3.2 = 1.32^n

ln(3.2) = ln(1.32^n)

ln(3.2) = n(ln(1.32)

n = ln(3.2) / ln(132)

n = 4.2, round to 4 weeks.