2. Solve the following proportion.
r over five equals nine over twenty-one (1 point)
r = 2.14
r = 9
r = 11.66
r = 37.8
r/5 = 9/21
multiply both sides by 5
so
r = 45/21
r = 2.14
thanks damon
Thanks Damon as always.
To solve the proportion "r over five equals nine over twenty-one," we can use the cross product method.
The cross product method involves multiplying the numerator of the first fraction by the denominator of the second fraction and setting it equal to the product of the denominator of the first fraction and the numerator of the second fraction.
In this case, we have:
r/5 = 9/21
To solve for r, we can cross-multiply:
21 * r = 5 * 9
Now, we simplify the equation:
21r = 45
To isolate r, we divide both sides of the equation by 21:
r = 45/21
Simplifying the fraction, we get:
r = 15/7
Therefore, the solution to the proportion is r = 15/7.