The answer is 12.5 seconds.
48/5 = 120/x
x = 2.5
2.5 * 5 = 12.5
Answer: 3/K
Step-by-step explanation:
From the question, we are informed that Mary bought K stamps for 3 dollars and we are told to find the cost of one stamp.
Number of stamps bought = K
Cost of K stamps bought = 3 dollars
Cost of ones stamp = Cost of stamps bought ÷ Number of stamps bought
= 3/K
Therefore, the cost of one stamp is 3/K
Answer: 30g
Step-by-step explanation:
In this question (t½) of isotope is 40 days, which means that after 40 days half of the sample would have decayed and half would be left as it is.
After 40 days ( first half life) 240 /2 = 120 g decays and 120 g remains left.
After another 40 days ( two half lives or 80 days) 120 /2 = 60 g decays and 60 g remains left .
after three half lives or 120 days, 60/2 = 30g decay and 30 g of the isotope will be left.
