It's scientific notation, so 1.4x10^7 would be 14000000 <span />
Answer:
43.16 mg
Step-by-step explanation:
After each hour, the amount remaining is 100% - 12% = 0.88 times the amount present at the beginning of the hour. Then after 8 hours, the amount remaining will be the initial amount multiplied by 0.88 eight times, or ...
(120 mg)·(0.88^8) ≈ 43.1561 mg ≈ 43.16 mg
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Of course, an exponent is used to signify repeated multiplication. You can actually do the multiplication if you like, but most scientific and graphing calculators handle exponentiation easily.
Answer:
The length of the arc is 4.6375 miles
Step-by-step explanation:
Firstly, find the perimeter of the circle by doing 2*pi*r, you'll get about 18.55 miles.
2*pi*r ---> 2*pi*3 ---> 6*pi ---> ≈ 18.55 miles
Next, plug in x/360, where 360 is the total arc of a circle, and x is the arc you need.
x/360 ---> 90/360 ---> = 0.25
Lastly multiply the two numbers.
18.55 * 0.25 ---> 4.6375 miles is your answer.
<em>(you may need to round your answer if needed)</em>
