Hi there! So, there are 40 doses in 1 bottle. To find out the number of doses in 3 1/3 bottles, we have to multiply both numbers together. 3 1/3 as an improper faction is 10/3. 40/1 * 10/3 is 400/3 or 133 1/3 in simplest form. There are 133 1/3 doses of medicine in 3 1/3 bottles.
If the perimeters are equal, you can form an equation to find x:
x + x + 12 + x + x + 12 = x + 11 + x + 11 + x + 16
4x + 24 = 3x + 38
- 3x
x + 24 = 38
- 24
x = 14
Now you can substitute the x value into the perimeter:
(4 × 14) + 24
56 + 24 = 80 cm
(3 × 14) + 38
42 + 38 = 80 cm
So the perimeter would be 80 cm.
I hope this helps!
Subtract t the first 2 choices from the total time:
10 - 3.2 - 3.5 = 3.3
The 3rd selection needs to be 3.3 minutes long