7th Grade Math

636 Measurement and Proportional Reasoning

Convert 828.5 milliliters to cups. Round to the nearest hundredth

if necessary.

Since 1 cup ≈ 236.59 milliliters, multiply by _1 c

236.59 mL.

828.5 mL ≈ 828.5 mL ·_1 c

236.59 mL

Multiply by

_1 c

236.59 mL^ and divide out

common units.

≈_828.5 c236.59 or 3.5 c Simplify.

So, 828.5 milliliters is approximately 3.5 cups.

Complete. Round to the nearest hundredth if necessary.

a. 7.44 c ≈ mL b. 22.09 lb ≈ kg c. 35.85 L ≈ gal

Convert Between Systems

SWIMMING An Olympic-size swimming pool is 50 meters long.

About how many feet long is the pool?

Since 1 foot ≈ 0.30 meter, use the ratio _0.30 m1 ft.

50 m ≈ 50 m ·_0.30 m1 ft Multiply by _0.30 m1 ft.

≈ 50 m·_0.30 m1 ft Divide out common units, leaving the desired unit, feet.

≈_50 ft0.30 or 166.67 ft Divide.

An Olympic-size swimming pool is about 166.67 feet long.

d. POOLS An NCAA regulation-size swimming pool is 25 yards

long. About how many meters long is the pool?

Examples 1 and 2 Complete. Round to the nearest hundredth if necessary.

1. 3.7 yd ≈  m 2. 11.07 pt ≈  mL 33 58.14 kg ≈  lb


2. 3.75 c ≈  mL 5. 4.725 m ≈  ft 6. 680.4 g ≈  lb

Example 3 7. SPORTS About how many feet does a team of athletes run in a

1,600-meter relay race?

8. FOOD Raheem bought 3 pounds of bananas. About how many kilograms
   did he buy?

Real-World Link

The National Aquatics

Center, also called the

Water Cube, built for

the 2008 Olympics in

Beijing consists of more

than 100,000 square

meters (or 1.08 million

square feet) of plastic

foils and is the largest,

most complicated,

plastic-covered structure

in the world.

RRR

T

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