Question

A newly hatched channel catfish typically weighs 0.3 grams. During the first 6 weeks of life, its growth is approximately exponential, increasing by about 10% each day. Find the weight at the end of four weeks. (Hint: Be sure to change the number of weeks to days before plugging into the formula!) Formula: A=C(1+r)t
0.53g
4.33g
16.43g
1.14g

Answer 1

Answer: second option 4.33 g

Explanation:

1) The formula is given: A = C(1+r)ˣ ↔ (I used x instead of t just do to limitations of the math editor. Keep in mind that here x is time in days.

2) r is the rate of increasing given: 10% = 10/100 = 0.1

3) C is the initial weight and A is the final weight after x (or t) days.

4) The equation leads to:

A = 0.3 (1 + 0.1)ˣ = 0.3(1.1)ˣ

x = number of days = 7 × number of weeks = 7 × 4 = 28 days

4)  Compute:

A = (0.3g)(1.1)²⁸

A = 4.33g ← answer