During a trip, francine traveled x percent of the total distance at an average speed of 40 miles per hour and the rest of the distance at an average speed of 60 miles per hour. in terms of x, what was francine`s average speed for the entire trip? a. (1800 - x) /2
b. (x + 60) /2
c. (300 - x ) / 5
d. 600 / (115 - x )
e. 12,000 / ( x + 200)

Correct C. (300 - x ) / 5

Step-by-step explanation:

Francine traveled x percent of distance at 40 miles per hour and 1-x at 60 miles per hour,

So,

Average speed would be the total distance / the time but in this case we need to calculate an average ponderated speed wich would be

x/100 * 40 + (1 - x/100) * 60 = 40/100 x + 60 - 60/100 x = ( 60 - 20/100 x ) = 60 - 1/5 x = (300 - x) / 5

idk

step-by-step explanation:

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!