Given:
15 students
2 students must be chosen.
No repetition, no order
This is a combinations problem. We use this formula: n! / (n-r)!(r!)
n = 15 ; r = 2
15! / (15-2)!(r!) ⇒ 15! / 13! * 2! = 105
Wouldnt this be something like x and y squared
1 1/2 - 2 1/2 is 3/2:5/2 or a 3:5 ratio
2 2/5 - 4 is 12/5:20/5 or a 3:5 ratio
3 3/4 - 6 1/4 is 15/4:25/4 or a 3:5 ratio
4 - 6 2/3 is 12/3:20/3 or a 3:5 ratio
1.2- 2 if divided by .4 is a 3:5 ratio
1.8-3 if divided by .6 is a 3:5 ratio
the unit rate is 3:5
Since all units are 3:5 it is proportional
Answer: 9
Step-by-step explanation:
An elf ate 15 of your muffins and that was 5/8 of all of them. To get the number of muffins left goes thus:
We can first calculate the total number of muffins the person had. Let the total number of muffins be y. That means the elf ate 5/8 of y.
5/8 of y = 15
5/8 × y = 15
0.625 × y = 15
0.625y = 15
Divide both side by 0.625
0.625y/0.625 = 15/0.625
y = 24
The total amount of muffins is 24. Since the elf has eaten 15, the amount left will be: 24-15 = 9
Answer:
Step-by-step explanation:
The first step is to combine like terms, and multiply them together first. Since multiplication is commutative, it doesn't matter in what order you do it. Therefore, this can be rewritten as 
. Hope this helps!
