3 + 5 = 8
1600/8 = 200
3 x 200 = 600
So the answer is 600
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We'll be assuming this is with simple interest.
now, a year has 12 months, thus in 18 months there are 18/12 years.

66 degrees
Add 30, 57, and 27, then subtract from 180
Let the 4 integers be x, x+2 , x+4 , x+6 Then
4x + 12 = 7(x + 6)
4x + 12 = 7x + 42
3x = -30
x = -10
The integers are -10 -8 , -6, and -4 answer