7th Grade Math

Lesson 3C Statistical Displays 523

6. ECLIPSES Use the histogram at
   the right.
   a. What percent of the solar
   eclipses lasted at least
   7 minutes 31 seconds?
   b. How long was the shortest
   solar eclipse?
   c. How many solar eclipses
   lasted between 1 second and
   5 minutes?

77 BUILDINGS Use the histograms shown.

a. Which city has the tallest building?

b. Determine which city has more buildings that are 800–899 feet tall.

c. Determine which city has more buildings that are at least 600 feet tall.

What percent of the buildings in that city are at least 600 feet tall?

d. Which city has more tall buildings? by how many?

B 8. COLLECT THE DATAConduct a survey of your classmates to determine the

number of hours each person spends on the Internet during a typical

week. Then construct a histogram of your data.

C 9. OPEN ENDED Construct a histogram that has a vertical line of symmetry

and two gaps. Then construct a histogram that has a vertical line of

symmetry and one gap.

10. CHALLENGE Describe how the histogram

Frequency

5 4 3 2 1 0

Age (yr)

0–4 5–9 10–14 15–19

at the right would change if larger

intervals, such as 0–9 and 10–19, were

used. Describe how it would change if

smaller intervals, such as 0–2, 3–5, 6–8,

and so on, were used.

11. E WRITE MATHCompare and contrast
    a bar graph and a histogram.

Solar Eclipses, 2001–2010

Number of Eclipses

Duration (minutes:seconds)

0:01–

2:30

2:31–

5:00

5:01–

7:30

10:01–

12:30

7:31–

10:00

0

1

2

3

4

5

6

7

Seattle, WA

Number of Buildings

Height (feet)

400–

499

500–

599

600–

699

800–

899

700–

799

900–

999

0

1

2

3

4

5

6

7

8

9

Pittsburgh, PA

Number of Buildings

Height (feet)

400–

499

500–

599

600–

699

800–

899

700–

799

900–

999

0

1

2

3

4

5

6

7

8

9

Real-World Link Tall Buildings in Pittsburgh and Seattle

Total solar eclipses

occur about 3 times

every 4 years.

RR

T

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