Answer:
There are 650 cannonballs
Step-by-step explanation:
If you look closely in the picture, you can see that:
- 1st row has 1 ball
- 2nd row has 4 balls
- 3rd row has 9 balls
- 4th row has 16 balls
etc. etc.
We can see that the number of balls is the square of the row number. There are a total of 12 rows. So, rest of the rows has:
- 5th row has 25 balls
- 6th row has 36 balls
- 7th row has 49 balls
- 8th row has 64 balls
- 9th row has 81 balls
- 10th row has 100 balls
- 11th row has 121 balls
- 12th row has 144 balls
If we add up all those, we get total number of balls:

There are 650 cannonballs
I think that the answer is c
Answer:
x = 35
Step-by-step explanation:
Solve for x:
6 x - 15 = 4 x + 55
Hint: | Move terms with x to the left hand side.
Subtract 4 x from both sides:
(6 x - 4 x) - 15 = (4 x - 4 x) + 55
Hint: | Combine like terms in 6 x - 4 x.
6 x - 4 x = 2 x:
2 x - 15 = (4 x - 4 x) + 55
Hint: | Look for the difference of two identical terms.
4 x - 4 x = 0:
2 x - 15 = 55
Hint: | Isolate terms with x to the left hand side.
Add 15 to both sides:
2 x + (15 - 15) = 15 + 55
Hint: | Look for the difference of two identical terms.
15 - 15 = 0:
2 x = 55 + 15
Hint: | Evaluate 55 + 15.
55 + 15 = 70:
2 x = 70
Hint: | Divide both sides by a constant to simplify the equation.
Divide both sides of 2 x = 70 by 2:
(2 x)/2 = 70/2
Hint: | Any nonzero number divided by itself is one.
2/2 = 1:
x = 70/2
Hint: | Reduce 70/2 to lowest terms. Start by finding the GCD of 70 and 2.
The gcd of 70 and 2 is 2, so 70/2 = (2×35)/(2×1) = 2/2×35 = 35:
Answer: x = 35
Find the area of the room by multiplying the length by the width:
Area of room = 20 x 12 = 240 square feet.
Find the area of the tile: 2x 2 = 4 square feet.
To find the number of tiles divide the area of the room by the area of a tile:
240/4 = 60
They will need 60 tiles.