12s + 5 = 77
12s = 77 - 5 = 72
s = 72/12
s = 6 ...//
Ans = C ... 12x + 5 = 77 ...
Answer:
3
15
Step-by-step explanation:
15 is the number that forms the ratio 3/7 of 35
follow the column up until the row 3
This is a linear equation or y=mx+c. Where y is the number of mosquitos at a particular month and x is the number of months. We know the initial population of the mosquitoes is c=20. They population doubles every month so this is the gradient, m=2. Therefore the equation for the growth of the mosquito population is:
y = 2x + 20.
So after x= 10 months the mosquito population will be,
y=2(10)+20= 40.
There will be 40 mosquitoes after ten months.
Suppose

is the number of possible combinations for a suitcase with a lock consisting of

wheels. If you added one more wheel onto the lock, there would only be 9 allowed possible digits you can use for the new wheel. This means the number of possible combinations for

wheels, or

is given recursively by the formula

starting with

(because you can start the combination with any one of the ten available digits 0 through 9).
For example, if the combination for a 3-wheel lock is 282, then a 4-wheel lock can be any one of 2820, 2821, 2823, ..., 2829 (nine possibilities depending on the second-to-last digit).
By substitution, you have

This means a lock with 55 wheels will have

possible combinations (a number with 53 digits).
16.7 is the answer rounded to the nearest tenth.