Answer:
at least 450 minutes
Step-by-step explanation:
Find an expression for the cost of each plan as a function of the number of minutes. Set the expressions equal to each other, and solve for the number of minutes.
Let x = number of minutes.
First plan:
cost (in dollars) = 0.21x
Second plan:
cost (in dollars) = 0.11x + 44.95
Set the expressions equal:
0.21x = 0.11x + 44.95
Subtract 0.11x from both sides.
0.1x = 44.95
Divide both sides by 0.1
x = 44.95/0.1
x = 449.5
Since you cannot have a fraction of a minute, the answer is 450 minutes.
Answer:
50 nickels, 20 quarters.
Step-by-step explanation:
System of equations (q = # of quarters, n = # of nickels):
<em>q + n = 70, 0.25q + 0.05n = 7.50</em>
the first equation can be changed to q = 70 - n, so we are able to <em>substitute q with 70 - n</em>.
So, it will look like <em>0.25*70 - 0.25n + 0.05n = 7.50</em>. This can be simplified to <em>0.2n = 10</em>, which means that n = 50.
Knowing that we can solve <em>q + 50 = 70</em>, which means that q = 20.
Answer:
B, 9.625
Step-by-step explanation:
I know there's a more surefire method of doing this problem but since this is multiple choice, you can use process of elimination to solve it.
9t = 27.99
5t = ?
Cross-multiply : 9t? = 139.95t
?=15.55
