Example 1 Solving an Inequality Using Multiplication

Simplify.n ≤ –16

Multiply each side by 8. Reverse inequality symbol.(Multiplication property of inequality)

281 n–8 • 8 • ≤– – –

Original inequality281 n ≥–

Example 2 Solving an Inequality Using Division

Original inequality15 > 3m –

Divide each side by 3. Reverse inequality symbol.(Division property of inequality)3

15<

33m–––

–

Simplify.5 < m–

Example 3 Using the Division Property of Inequality

About 15,000 fruit-eating bats live on Barro Colorado Island. They eat up to 61,440,000 grams of fruit yearly. Write and solve an inequality to find up to about how many grams g of fruit each bat eats yearly.

BIOLOGY

SOLUTION

Write an algebraic model.15,000g ≤ 61,440,000

Example 3 Using the Division Property of Inequality

Simplify.g ≤ 4096

Divide each side by 15,000.15,000

15,000g≤

15,00061,440,000

ANSWER

Each bat eats up to about 4096 grams of fruit in a year.

for Examples 1, 2, and 3Guided Practice

1. Solve the inequality > 4.6t

ANSWER t > 24

ANSWER t > – 9

2. Solve the inequality 27 > 3t.–

for Examples 1, 2, and 3Guided Practice

3. BIOLOGYA bat that weighs about 25 grams can eat up to 2.5 times its body mass in figs in one night. Up to how many grams g of figs can it eat?

ANSWER 62.5 g