In order to get the common denominator when adding fractions or subtracting fractions, you have to make sure that the denominator of the two items are divisible by each other. In this case, 9 is not divisible by any of the given denominators which is 4 and 5. So in this case, the common denominator will have to be 20. 5 x 4 will equal to 20 and you will also multiply 3 x 5 to get the new numerator. After that, you will multiply 2 x 4 to get the new numerator of the other fraction. The new fractions will be 15/20 and 8/20. From there, you can add or subtract
A total of 1,716 selections of the 7 flowers are possible.
Step-by-step explanation:
Step 1:
There are 13 flowers from which Jeanine Baker plans to use 7 of them.
To determine the number of selections that are possible we use combinations.
The formula for combinations is;
.
Step 2:
In the given formula, n is the total number of options and r is the number of options to be selected.
For this question,
and
.
So 
So a total of 1,716 selections are possible.
Fewer meters, centimeters are too small of a unit to measure a doorway