Here, y = -15 with x = -20
LCM of 15 & 20 is 60, so divide 15 & 20 from 60,
60/15 = 4 & 60/20 = 3
Now, multiply the results with intial values,
4y = 3x
y = 3/4 x
When y = 12,
x = 12 * 4/3
x = 48 / 3
x = 16
In short, Your Answer would be 16
Hope this helps!
Answer:
1.33 years.
Step-by-step explanation:




Let x = the next score
If (81 + 89 + 90 + 83 + 77 + x) ÷ 6 = 82
⇒ 420 + x = (82 × 6)
⇒ x = 492 - 420
x = 72
Thus to get an 82 average he need to get 72 on his next test.