A school bus has 25 seats, with 5 rows of 5 seats. 15 students from the first grade and 5 students from the second grade travel in the bus. How many ways can the students be seated if all of the second-grade students occupy the first row?
a. 25P20
b. 5P5 × 20P15
c. 5C5 × 25C14
d. 5P5 × 15P15
e. 5P5 × 25C15

Question

A school bus has 25 seats, with 5 rows of 5 seats. 15 students from the first grade and 5 students from the second grade travel in the bus. How many ways can the students be seated if all of the second-grade students occupy the first row?
a. 25P20
b. 5P5 × 20P15
c. 5C5 × 25C14
d. 5P5 × 15P15
e. 5P5 × 25C15

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