solve for N 5/16=n/80?

5/16=n/80

n = 80 x 5/16

n = (8 x 10 x 5)/16

n = (8 x 2 x 5 x 5)/16

n = (16 x 5 x 5)/16

cancel 16

n = 5 x 5

n = 25

5/16 = n/80
5 = 16(n/80)
5 = 16n/80
5 = n/5
n = 5(5)
n = 25

x represents multiplication.
5/16 =n/80
transfer 16 and 80 they change to multiplication.
5x80 =16n
400=16n
400/16=n
25=n
n=25
Hope This Helps.

400 = 16 n

n = 400 / 16

n = 100 / 4

n = 25

multiply both sides by 80, then simplify

400/16 = n = 25

5/16 = n/80

Cross multiply:
16n = 5 * 80
16n = 400

Divide by sixteen on both sides to get your N term by itself on one side.

n = 25

Either cross multiply and simplify, or multiply both sides by 16/5 (which will kill the 5/16), or multiply the whole thing through by the LCD of 80 which will clear the fractions.