3
Step-by-step explanation:
Answer:
(50+40x) dollars
Step-by-step explanation:
THe fixed cost is $50 (this includes everything and 6GB of data).
Now, for every GB <em>OVER</em> 6 GB he uses, company charges $40 extra.
So, if he used "x" GB EXTRA, his EXTRA cost will be 40 * x = 40x
Thus, his total cost in the month would be fixed cost PLUS the extra, which would be
50 + 40x dollars
Answer:
11 yrs
Step-by-step explanation:
Mean = sum of ages/number of ages
Let the age of the seventh girl be A
Given the addition of the age of the seventh girl will make the mean of the ages be 13,
So,
13 = 17+8+12+15+15+13+A/7
Add up the ages
13 = 80 + A /7
Cross multiply
80 + A = 13 x 7
80 + A = 91
Subtract 80 from both sides to isolate A
80 - 80 + A = 91 - 80
A = 11
The age of the seventh girl is 11
The goal of all algebra equations is to isolate the variable. In 3 step you should first make sure both variables are on the same side. To do that make sure you use the inverse.
For example:
6a + 9 = 3a + 15
because 3a is positive you're going to want to subtract it.
6a + 6 = 3a + 15
-3a -3a
_______________
3a + 6 = 15
Now it's a 2 step equation and you solve it on from there.