You know the following information:
1. The amount of money (in dollars) earned last year was:
2. The amount of money (in dollars) earned this year, is:
Then, to estimate the sum (the total amount of money the Software Company earned in those two years, you can round the numbers to the nearest billion.
Having:
You need to look at the digit located in the Hundred millions place. Notice that this is:
Then, since:
You need can't round up. Then:
Now, having:
You can identify that the digit in the Hundred millions place is
Therefore:
Now you can add the numbers rounded:
Hence, the answer is: Option B.
Answer:
A₍ₙ₎ = - 74 + (n-1) x 6
Step-by-step explanation:
A₍ₙ₎ = A₍₁₎ + (n-1) x d
A₍₁₈₎ = 28 = A₍₁₎ + 17 x d ..... (1)
A₍₄₀₎ = 160 = A₍₁₎ + 39 x d .....(2)
(2)-(1) 132 = 22d
d = 6
A₍₁₎ = 28 - 17 x 6 = -74
formula: A₍ₙ₎ = - 74 + (n-1) x 6
Answer:
the answer is 4.625 or 4 6/10
Step-by-step explanation:
I just used a calculator. hope this helps <3
Answer:
A. 77.4
Step-by-step explanation:
<u>Linear approximation formula</u>
Given function:
Use the chain rule to differentiate the function.
Differentiate the two parts separately:
Put everything back into the chain rule formula:
.
The <u>linear approximation</u> at a = 8 is:
Finally, substitute x = 7.8 into the <u>linear approximation equation</u>:
The half-life of Po is 139 days, so its decay rate is
0.5 = e^(139k) ==> k = ln(0.5)/139
After some time t, 80% of the material will have decayed and you'll be left with a sample 20% of its original mass:
0.2 = e^(kt) ==> t = ln(0.2)/k = ln(0.2)/ln(0.5) * 139 = 322.748
so your sample is usable for about 323 days.
