9514 1404 393
Answer:
7.92 years
Step-by-step explanation:
We want to find t such that ...
3 = 2^(t/5)
where 2^(t/5) is the annual multiplier when doubling time is 5 years.
Taking logs, we have ...
log(3) = (t/5)log(2)
t = 5·log(3)/log(2) ≈ 7.92 . . . years
It will take about 7.92 years for the population to triple.
Answer:
The number of baseball card to begin with is 143
Step-by-step explanation:
Let The number of baseball cards = x
The number of sold baseball card = 60% of x
= 0.6 x
The number of left baseball card = x - 0.6 x = 0.4 x
The number of card gave away = 30 % of left cards
= 0.3 × 0.4 x = 0.12 x
The number of card left in his possession = 40
So, 0.6 x + 0.12 x + 40 = x
Or, 40 = x - 0.6 x - 0.12 x
Or, 40 = 0.28 x
∴ x =
= 142.85 ≈ 143
Hence The number of baseball card to begin with is 143 Answer
1) 0.78
2) 34.28
This is because the number in the 3rd decimal place for both numbers is 5 or above so it is rounded up rather than down.