Answer:
see below
Step-by-step explanation:
4.2 x 10^6 − 1.2 x 10^5 − 2.5 x 10^5
All exponent have to have the same number
42 x 10^5 − 1.2 x 10^5 − 2.5 x 10^5
Subtract the number
42 - 1.2 - 2.5 = 38.3
Add back the exponent
38.3 * 10 ^5
This is not in scientific notation
Move the decimal one place to the left and add one to the exponent
3.83 * 10^6
3.3 x 10^9 + 2.6 x 10^9 + 7.7 x 10^8
All exponent have to have the same number
3.3 x 10^9 + 2.6 x 10^9 + .77 x 10^9
Add the numbers
3.3+2.6+.77 =6.67
Add back the exponent
6.67*10^9
This is in scientific notation
8.0 x 10^4 − 3.4 x 10^4 − 1.2 x 10^3
All exponent have to have the same number
8.0 x 10^4 − 3.4 x 10^4 − .12 x 10^4
Subtract
8.0 - 3.4 - .12 = 4.48
Add back the exponent
4.48* 10^4
This is in scientific notation
Answer:
37.5 miles per hour
Step-by-step explanation:
The question might be trying to confuse the reader. Point (1) which states the difference in weight does not show any evidence on how it affects the speed of both cyclist. Point (2) show an important point where the distance traveled is 75 miles.
Cyclist B, who leave point X at 2pm overtook cyclist A at 4pm, showing that the time it took for B to overtook A is 2 hours
Speed = distance / time
= 75 miles / 2 hours
= 37.5 miles per hour
We know that 1/2 and above rounds up and below 1/2 rounds down
3/10 is lower than 1/2
When you round down you get 20
Your answer is 20
Hope this helped!