Answer:
18 minutes
Step-by-step explanation:
A = A₀ (½)^(t / T)
where A is the final amount,
A₀ is the initial amount,
t is the time,
and T is the half life.
A = 140 when t = 10. Solve for the half life:
140 = 700 (½)^(10 / T)
0.2 = ½^(10 / T)
log 0.2 = (10 / T) log 0.5
10 / T = 2.32
T = 4.31
When A = 40, t is:
40 = 700 (½)^(t / 4.31)
0.057 = ½^(t / 4.31)
log 0.057 = (t / 4.31) log 0.5
t / 4.31 = 4.13
t = 17.8
Rounded to the nearest whole number, it takes 18 minutes.
Answer:
If 12,000 are put at an account with 2.5% compound interest in 15 years your total would be $17,379.58
Answer:
i think if she buys 5 books the she will have 90 stamps cuz 1 book cost 18 stamps then 5 books = <u>18x5=90</u>
Step-by-step explanation:
Answer:
14/20
Explanation:
Sasha tried to get a marble 20 times. 14 of those times she got a yellow marble.
The experimental probability, which is the probability of choosing a yellow marble when Sasha actually tries choosing marbles from the bag.
The theoretical probability is based on the chance that Sasha will get a yellow marble, 7/70, is from the amount of marbles in the bag of yellow colour.