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At Salisbury Central School, 60% of the students are 7th graders, and the

rest are 8th graders. Half of the 7th graders ride a bus to school, 20% of the
remaining 7th graders arrive by car, and the rest walk to school. A quarter of
the 8th graders ride a bus to school, a third of the remaining 8th graders arrive
by car, and the rest walk to school. What percent of Salisbury Central School
students walk to school?

User PEM
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1 Answer

5 votes

For 7th graders:
- Bus riders: 60% * 0.5 = 30%
- Car riders: 60% * (1 - 0.5) * 0.2 = 6%

For 8th graders:
- Bus riders: 40% * 0.25 = 10%
- Car riders: 40% * (1 - 0.25) * (1/3) = 8%

Now, add up the percentages for both grades:
30% (7th graders on the bus) + 6% (7th graders in cars) + 10% (8th graders on the bus) + 8% (8th graders in cars) = 54%

Subtract this total from 100% to find the percentage that walks: 100% - 54% = 46%

Therefore, 46% of Salisbury Central School students walk to school.
User Pedro Massango
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