2 classes of 21 students each
21 × 2 classes = 42 students in total
42 × 3 mins = 126 minutes for 42 students
10 mins for 2 class pics = 20 minutes
126 + 20 = 146 minutes = 2 hours and 26 minutes
It should take 146 minutes (2 hours and 26 minutes) to take all the pictures.
2 9/15 and 1 5/15 are your answers
Answer:
Explanation:
3 + 2x - y = 0
Or 2x - y = -3 (1)
-3-7y = 10x
Or -10x - 7y = 3 (2)
2x - y = -3 (1)
-10x - 7y = 3 (2)
———————
Multiply 5 to (1)
5(2x - y = -3)
-10x - 7y = 3
———————
10x - 5y = -15
-10x - 7y = 3
———————
-12y = -12
y = -12/-12
y = 1
Plug y value in (1)
2x - 1 = -3
2x = -3 + 1
2x = -2
x = -2/2 = -1
Therefore, x = -1 and y = 1