If the half-life is t, then every t days, the amount of the radioactive isotope will be cut in half.
(1/2)^(number of half-lives) = 3%
number of half-lives = ln(0.03) / ln(0.5)
This gives the number of half-lives as 5.06.
Then 300 days = (5.06)(length of 1 half-life)
length of 1 half-life = 300 / 5.06 = 59.29 days
Answer:
20 lbs
Step-by-step explanation:
2/5ths of the food would be 20 pounds because:
2/5 * 50 = 20
2/10ths of the food would be 10 pounds because:
2/10 * 50 = 10
If we add those two together, we would get the total amount that the dog ate, which would be 30 pounds. SInce the dog ate 30 pounds of food out of the 50 pounds, there would be 20 pounds left in the bag at the end of two months:
50- ( 20+ 10) = 20
Answer:
2{3[9+4(7-5)-4]}
2{3[9+4(2)-4]}
2{3[13(2)-4]}
2{3[26-4]}
2{3[22]}
2{66}
132
Step-by-step explanation:
First, you must change all of this into improper fractions, like shown below.
Now you must change the sign.
Then we must reciprocalize 2/3.
Now we multiply, to get 2 4/10.
third option is the correct answer....
