# 4.4. Practice question answers

# Chapter 4 practice question answers

**4.1. Exponential Functions**

**1.** ≈ 23.2%

**2.** B(t) is growing faster, but after 3 years A(t) still has a higher account balance.

**3.** 401.0071 , or about 401 people.

**4.** $4048.06

**5.** ≈ 950 ants

**6.** ≈ 0.59 cents

**4.2. Logarithmic Functions**

**1.** log_{4}(16) = 2

**2.** 6

**3.** -2ln(x)

**4.**

**5.** 5

**6.** -3

**7.** ≈ 10.8, or nearly 11 years.

**4.3. Exponential and Logarithmic Models**

**1.** ≈ 4.1874 weeks.

**2. **≈ 11.68 years.

**3.** ≈ 229.32, or approximately 229 years.

**4. a. **99.7%

** b. **97.2%

** c. **74.9%

**5.** 10.845, or approximately 11 years.

**6.** ≈ 9.9%.