X-7=13
move -7 to the right side of the equation, change the sign from negative to positive when you move it
x-7+7=13+7
x=13+7
x=20
Answer:
boys = 250
girls = 150
Step-by-step explanation:
5g = 3b eq. 1
g + b = 400 eq. 2
g = girls
b = boys
From the eq. 2
g = 400 - b
Replacing this last eq. on eq. 1:
5(400-b) = 3b
5*400 + 5*-b = 3b
2000 - 5b = 3b
2000 = 3b + 5b
2000 = 8b
2000/8 = b
250 = b
From eq. 2
g + 250 = 400
g = 400 - 250
g = 150
Check:
from eq. 1
5*150 = 3*250 = 750
Answer:
its 23.76
Step-by-step explanation:
I answered in the comments, but now I answered legit (there was a virus earlier lol)
Mean is average. Multiply total books by the mean to find the total cost:
5x 10 = $50 total.
Subtract the highest and lowest prices to find the total of the remaining 3 books.
50 - 15-6 = 29
The median price was 8, this is the middle number, subtract 8 from 29 to get the cost of the last 2 books:
29-8 =21
Now you need a price lower than the median but higher than the lowest cost so that has to be 7
Subtract 7 from 21 to get the cost of the last book 21-7 = 14
The price of the remaining books is $7 and $14