During a school excursion, each student from the junior school was charged 325 and each student from the senior school was charged 400. If there were 80 students from junior school and the combined average amount charged per student was 352, then how many students from senior school went for the excursion?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 45.
Let the number of students in senior school be x
The total amount charged from the junior student's school = 325 × 80 = 26000
The total amount charged from the senior student's school = 400 × x = 400x
The total amount charged from both schools
⇒ (x + 80) × 352
⇒ (x + 80) × 352 = 26000 + 400x
⇒ 352x + 28160 = 26000 + 400x
⇒ 400x - 352x = 28160 - 26000
⇒ 48x = 2160
⇒ x = 45
Hence,
The number of students in the senior school who went on the excursion = 45