Answer:
-4
Step-by-step explanation:
You have too divide 2 and 7 and 8 divided by the sum and that’s your answer
Answer:
60.5 milligrams per square centimeter First, determine how many half lives have expired by dividing the time by the half-life. So: 55/20 = 2.75 That means that only 2^(-2.75) = 0.148650889 = 14.8650889% of the original substance remains. So just divide the amount remaining by 0.148650889 to get the original amount. 9 / 0.148650889 = 60.5445419 So originally, there was 60.5 milligrams per square centimeter 55 years ago.
Answer:
y = 60 when x = 12
Step-by-step explanation:
Direct variation is
y = kx
15 = k3
Divide by 3
15/3 = k
5 =k
y = 5x
Let x = 12
y = 5*12
y = 60
