Answer:
Original number 26.
Step-by-step explanation:
xy - two-digit number
1) x + y = 8
2) Original two-digit number can be written as
10*x + y
3) If the digits interchanged yx,
then the new number can be written as
10*y + x
4) Double the original number is
2*(10*x + y)
5) New number is 10 more than double the original number
(10*y + x) - (2*(10*x + y)) = 10
6) Now we have the system of 2 equations:
x + y = 8
(10*y + x) - (2*(10*x + y)) = 10 -----> 10y + x - (20x + 2y) = 10 ---> 8y - 19x = 10
x = 8 - y
8y - 19(8 - y) = 10
8y - 152 +19y = 10
27y = 162
y = 6
x = 8 - y = 8 - 6 = 2
x = 2
So, x =2, y = 6.
Original number 26.
Check:
Original number 26.
New number 62.
Double of the original number = 2*26= 52.
New number is 10 more than double the original number :
62 - 52 = 10 True
Answer:
$ 35 .00
Step-by-step explanation:
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Answer:
Step-by-step explanation:
Slope is an average. In this particular context, the slope of 6.9 (or 7) means that an average of 7 people entered the store every hour.
If x is the number of hours the store is open and we are told to find the number of customers that have entered the store after 5 hours, we fill in the equation as follows:
y = 7(5) + 10 and
y = 35 + 10 so
y = 45.
If you use 6.9 instead of 7:
y = 6.9(5) + 10 and
y = 34.5 + 10 so
y = 45.5
Since you can't count a half of a person, using 7 instead of 6.9 makes more sense.
