The key information here is the time he took to run the race - 420 seconds
We know that there are 60 seconds in 1 minute so to find the number of minutes we divide 420 by 60 to get 7.
Murad took 7 minutes to run the race
This question is a piece-o-cake if you know the formulas for the area and volume of a sphere, and impossible of you don't.
Area of a sphere = 4 π R² (just happens to be the area of 4 great circles)
Volume of a sphere = (4/3) π R³
We know the area of this sphere's great circle, so we can use the
first formula to find the sphere's radius. Then, once we know the
radius, we can use the second formula to find its volume.
Area of 4 great circles = 4 π R²
Area of ONE great circle = π R²
225 π cm² = π R²
R² = 225 cm²
R = √225cm² = 15 cm .
Now we have a number for R, so off we go to the formula for volume.
Volume = (4/3) π R³
= (4/3) π (15 cm)³
= (4/3) π (3,375 cm³)
= 14,137.17 cm³ (rounded)
This answer feels very good UNTIL you look at the choices.
_____________________________________________________
I've gone around several loops and twists trying to find out what gives here,
but have come up dry.
The only thing I found is the possibility of a misprint in the question:
If the area of a great circle is 225π cm², then the sphere's AREA is 900π cm².
I'm sure this is not the discrepancy. I'll leave my solution here, and hope
someone else can find why I'm so mismatched with the choices.
Answer:
x=-32/29
Step-by-step explanation:
3x+4y=36 Equation 1
-5x+3y=35 Equation 2
Multiplying equation 1 with 3 (value before y in equation 2) and equation 2 with 4 (value before y in equation 1) we obtain equations 3 and 4 as follows
9x+12=108 equation 3
-20x+12y=140 equation 4
Subtracting equation 3 from equation 4 we obtain
-29x=32
x=-32/29
To find the value of y, we substitute the value of x into equation 2 as initially given in the equation
-5(-32/29)=35-3y
-5(-32/29)-35=-3y
Answer:
57.76 :)
Step-by-step explanation:
