Question

Question 4 Part A (5 points):

Carlos started a business growing palm trees in South Florida.
The function t(s) = 3s + 20 represents the
number of palm trees that grew, where s is the
number of seeds he planted.
The function s(d) = 20d represents the number
of seeds he plants per day, where d represents
the number of days.
Write a composite function that represents
how many palm trees Carlos can expect to
grow over a certain number of days.

Answer 1

t(d) = 60d + 20

where t(d) is the number of palm trees grown, and d is the number of days

Explanation:

Given function:

t(s) = 3s + 20

where:

• t(s) = number of palm trees grown
• s = number of seeds planted

Given function:

s(d) = 20d

where:

• s(d) = number of seeds planted per day
• d = number of days

To determine the composite function that represents how many palm trees Carlos can expect to grow over a certain number of days, simply substitute s = 20d into t(s) = 3s + 20:

⇒ t(d) = 3(20d) + 20

⇒ t(d) = 60d + 20

where t(d) is the number of palm trees grown, and d is the number of days.