Abag contains 57 coins which are only quarters and dimes the total value of coins is $9.45 how many dimes are in the bag

There are 32 dimes and 25 quarters.

Step-by-step explanation:

q + d = 57 or q = 57 - d  

25q + 10d = 945  

substitute first equation into second equation:  

25(57 - d) + 10d = 945  

1425 - 25d + 10d = 945  

-15d = -480  

d = -480/-15 = 32  

using first equation:  

q = 57 - 32 = 25  

check using second equation:  

25(25) + 10(32) = 945 checks

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!