Answer:
15
Step-by-step explanation:
N:18 = 30:36
make N:18 and 30:36 a fraction
N/18 = 30/36
cross multiply 30 and 18, the answer is 540.
to get the missing number to make it a proportion is 540 divided by 36= 15, so the missing number is 15, or N is equal to 15.
hope it helped. :))
