<span>The key step is to rewrite the exponential notations so that the exponent is the same. Then you can deal with the addition just as you would adding two decimals. The best way is to rewrite the number with the smaller exponent.
6.30 x 10^11 = 0.0630 x 10^13
Now you are adding 6.28 x 10^13 and 0.0630 x 10^13, and your answer is (6.28 + 0.0630) x 10^13. You can do the addition in the parentheses using the usual rules for sig dig when you add decimals. If necessary, afterward, you can rewrite the exponent again so that the mantissa is between 1 and 10.</span>
Answer:
C. 
Step-by-step explanation:
c
Answer:
$113
Step-by-step explanation:
Since he had $13 and now he is $100 in debt:
First, he withdrew $13 to get $0 in his bank account.
He then withdrew $100 to get -$100 in his bank account.
13 + 100 = 113
$20.00 ≥ 7.50+1.25x
subtract 7.50 from both sides
20-7.50=12.50
12.50=1.25x
12.50/1.25=10
x= 10 rides
