Answer:
Step-by-step explanation:
the first day he used 30 cups
the second day he used 15% of the remaining cups...a total of 90 cups were used on second day.
so 15%of the remaining cups = 90.....so if u let x be the total cups, then the remaining cups would be x - 30
15% of (x - 30) = 90.....turn ur percent to a decimal..." of " means multiply
0.15(x - 30) = 90
0.15x - 4.5 = 90
0.15x = 90 + 4.5
0.15x = 94.5
x = 94.5 / 0.15
x = 630 total cups <==
lets check..
start with 630 cups....used 30 the first day....leaving u with 600 cups....15% of the remaining cups = 90.....so 15% of 600 = 90....lets check it
15%of 600 = 0.15(600) = 90...yep, thats correct....there were 630 cups in the new un-opened box
All you have to do is the amount she bought divided by 0.05 and then add the answer you get to the amount she bought each time
Just add 3 to both sides
x = 7
Answer:
6
Step-by-step explanation:
3x+6+5x+10=64
3x+5x+6+10=64
8x+16=64
8x=64-16
8x=48
divide both sides by 8
x=6
Answer:
560 ft/min
Step-by-step explanation:
Let r represent Samantha's running rate in feet per minute. Then r-230 is her walking rate. We can use the relation ...
distance = speed × time
to write an equation for the total distance Samantha went.
20r + 15(r -230) = 16150
35r - 3450 = 16150 . . . . eliminate parentheses, collect terms
35r = 19600 . . . . . . . . . . add 3450
r = 560 . . . . . . . . . . . . . . divide by the coefficient of r
Samantha ran 560 feet per minute.
