7th Grade Math

188 Rational Numbers

Replace each with <, >, or = to make a true sentence.

34. 1.8 × 103  1.9 × 10 –^1 35. 5.2 × 102  5,000


35. 0.00701  7.1 × 10 –^3 37. 6.49 × 104  649 × 102


36. MEASUREMENT The table at the right shows the values Metric Measures
    Prefix Meaning
    atto 10 -^18
    giga 109
    kilo 103
    nano 10 -^9
    peta 1015
    pico 10 -^12

of different prefixes that are used in the metric

system. Write the units attometer, gigameter,

kilometer, nanometer, petameter, and picometer in

order from greatest to least measure.

B 39. NUMBER SENSE Write the product of 0.00004 and

0.0008 in scientific notation.

40. NUMBER SENSE Order 6.1 × 104 , 6,100, 6.1 × 10 –5,
    0.0061, and 6.1 × 10 –^2 from least to greatest.

4141 PHYSICAL SCIENCE The table shows the maximum amounts of lava in

cubic meters per second that erupted from four volcanoes.

Volcanic Eruptions

Volcano, Year Eruption Rate (m (^3) /s)
Mount St. Helens,
1980 2 ×^10
4
Ngauruhoe, 1975 2 × 103
Hekla, 1970 4 × 103
Agung, 1963 3 × 104
a. How many times greater was the Mount St. Helens eruption than the
Ngauruhoe eruption?
b. How many times greater was the Hekla eruption than the Ngauruhoe
eruption?
Write each number in standard form.

42. (8 × 100 ) + (4 × 10 –^3 ) + (3 × 10 –^5 )


43. (4 × 104 ) + (8 × 103 ) + (3 × 102 ) + (9 × 101 ) + (6 × 100 )


44. MULTIPLE REPRESENTATIONS A square piece of property has a side of
    3,250 feet.
    a. ALGEBRA Write an equation to 3,250 ft

3,250 ft

represent the area of the property

in square feet.

b. ALGEBRA Solve the equation in part a

to find the area of the property.

c. NUMBERS Express the area in scientific

notation.

Real-World Link

Mount St. Helens is

located in the state of

Washington about

100 miles south of

Seattle. The height of

Mount St. Helens was

9,677 feet before the

1980 eruption and

8,363 feet after the

eruption.

RRR

M

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