Step-by-step explanation:
A. When dealing with large numbers, sometimes it's easier to write them in a form of exponents of number ten. The value of the exponent shows how many times we multiply 10 by itself. That means that 10^3 is 10•10•10 or that 10^6 is 10•10•10•10•10•10.
So, when finding how many times on number is greater then the other, we need to divide them. We divide 8x10^6 by 2x10^5. It is done by dividing the numbers and subtracting the exponents; 8/2=4 and 10^6/10^5 is 10^6-5=10^1. So the correct answer is 4x10^1 which is 4x10, and that is 40.
B. Now, we have a total number of coins (2.25x10^5), and diametar of a coin (19mm = 19x10^-6km). Our task is to calculate the distance across which the coiks laid side-by-side would expand. We can find this by multiplying the number of coins with a diametar of single penny, 2.25x10^5•19x10^-6. Multiplying is done by multiplying the numbers (2.25x19=42.75) and adding the exponents (5+(-6)=5-6=-1). So, the distance is 42.75x10^-1km, which equals to 4.275 km. Obviously, this is less then the stated 5 km given in the text, so the reportet's statement is false.
Answer: 2 19/24 hours was spent in practising.
Step-by-step explanation:
During the first hour, they practiced for 5/8 of an hour. During the second hour, they practiced for 2/3 of an hour. This means that the total time for which they practiced in the first 2 hours would be
5/8 + 2/3 = 31/24 hours
During the last two hours, they first practiced for 3/5 of an hour, took a 1/2 hour break and then practiced the rest of the time. This means that the rest of the time for which they practiced is
2 - (3/5 + 1/2) = 2 - 11/10 = 9/10
Therefore, the time they spent practicing in total would be
31/24 + 3/5 + 9/10 = 67/24 =
2 19/24 hours
Fnfnf kenzie said i had trttttttttt
100/100 x 85/100x 23/100=
Area of a circle = 3.14 x r^2
=3.14 x 8.5^2
= 226.865