If we know that 30% of the time is used after 9 minutes we can write this mathematically as:

By solving for x we can determine the total time allowed to play games and so:

The total time allowed to play games is 30 minutes. Since 9 minutes have lapsed 30-9=21 minutes left to play.
Answer:
D<Q≤2 Or D<Q Q+D≤2
Step-by-step explanation:
I'm pretty sure this is the answer but it's been a while since I've done system of inequalities. Essentially the value and number of dimes is less than the value and number of quarters. And the value of both is less than or equal to 2 dollars
Answer:
I likr=e the Story 12
Step-by-step explanation:
I really like how they jump and 1+1=2 right or is it 3???
Hmmm...
Answer:
Number of nickels = 17
Number of dimes = 23
Step-by-step explanation:
Let
x = number of nickels
y = number of dimes
x + y = 40 (1)
0.05x + 0.10y = 3.15 (2)
From (1)
x = 40 - y
Substitute x = 40 - y into (2)
0.05x + 0.10y = 3.15 (2)
0.05(40 - y) + 0.10y = 3.15
2 - 0.05y + 0.10y = 3.15
- 0.05y + 0.10y = 3.15 - 2
0.05y = 1.15
y = 1.15/0.05
y = 23
Substitute y = 23 into (1)
x + y = 40 (1)
x + 23 = 40
x = 40 - 23
x = 17
Number of nickels = 17
Number of dimes = 23