Answer: 21
Step-by-step explanation: To solve this problem, we can first set up a proportion because we know that 3 is to 7 as 9 is to x.
So we have
.
Now, we can use cross products to find the missing value.
So we have 3 time x which is 3x and 7 times 9 which is 63.
Rewriting our equation, we have 3x = 63.
Dividing both sides by 3, we find that <em>x = 21</em>.
So, <em>x = 21</em>.
The red arrows in the middle mean that they are parallel so the slopes are the same.
Ok, so we can fill the part of the box that corresponds to the 8x4 inches with the boxes that are 1 cubic inch - that wound be 8x4, that is 32 such boxes.
then the rest would be 8x

inches, that is 4 cubic inches.
In order to fill in 4 cubic inches with

inches boxes we calculate:

So it's also 32 such small boxes!
Solution:
<u>Note that:</u>
- Area of triangle = 6 3/8 yd²
- Height of triangle = 2 1/2
- Area of triangle = 1/2 x base x altitude
<u>Use the formula to find the base of the triangle.</u>
- 1/2 x base x altitude = 6 3/8 yd²
- => 1/2 x base x 2 1/2 = 6 3/8 yd²
- => 1/2 x base x 5/2 = 6 3/8 yd²
- => 5/4 x base = 6 3/8 yd²
- => base = 6 3/8 ÷ 5/4 yd
- => base = 51/8 x 4/5 yd
- => base = 51/2 x 1/5 yd
- => base = 51/10 yd
The length of the base is 51/10 yards.