Darryl wants to add enough water to 8 gallons of a 10% bleach solution to make a 5% bleach solution. Which equation can he use to find x, the number of gallons of water he should add? Original
(Gallons)
Added
(Gallons)
New
(Gallons)
Amount of Bleach
0.8
0
0.8
Amount of Solution
8
x
8 + x

StartFraction 0.8 Over 8 + x EndFraction times StartFraction 5 Over 100 EndFraction = 1
StartFraction 0.8 Over 8 + x EndFraction times = StartFraction 5 Over 100 EndFraction
StartFraction 0.8 Over 8 + x EndFraction = StartFraction 100 Over 5 EndFraction
StartFraction 0.8 Over 8 + x EndFraction divided by StartFraction 5 Over 100 EndFraction = 1

this may not be at all, but i use the same website you're using for school, and if i'm stuck doing one of these i try to look for it on the section.

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!