Answer:
<em>3 hours</em>
Step-by-step explanation:
Given that:
Average speed of Willie = 40 km/h
After 2 hours, Gabriella traveled in opposite direction at an speed of 70 km/h.
After some time, they are 410 km apart.
To find:
Number of hours = ?
Solution:
For the first two hours, Willie traveled alone.
Formula for distance:

Distance traveled in two hours by Willie = 
Now, they both travel in opposite directions.
So the relative speed is = 40 + 70 = 110 km/h
The distance traveled by them = 410 - 80 = 330 km

Therefore, the time taken is <em>3 hours.</em>
Answer:
I am not sure but I think a or d is answer
I'm not quiet sure
84. Area of a triangle is (base x height) / 2
<u>Answer:</u>
The Ranking Percentile is (B) 97.5%
<u>Explanation
:</u>
To find the percentile rank we need to find the z- score. After finding the z-score match this value with the corresponding value in z-score table.
Formula to find the z-score
Z-score=
Substituting the values in the above equation, we find
Z-score=
=2
So, the Z-score is +2
Now, the corresponding value of Z-score 2 in the table is 0.9772
or the percentile score is 97.72 ~ 97.5
.
Answer:
The new volume is 1/343 of the old volume or the ratio of the new volume to the old volume is 1 to 343
Step-by-step explanation:
In this question, we are asked to state the effect of multiplying the radius of a sphere by 1/7 on the volume.
Mathematically, the volume of a sphere V can be calculated using the formula
V = 4/3 * π * r^3
Now multiplying the radius by 1/7, the new radius will be r/7
Thus the new volume here will be
V2 = 4/3 * π * (r/7)^3
V2 = 4/3 * π * (r^3)/343
Thus we can conclude that the value of the volume will be decreased by a factor of 343
Meaning the ratio of the old volume to the new volume will be 1 to 343