Answer:
Step-by-step explanation:
4/20 + 11/20 = 15/20
15/20 = 3/4 or 0.75
First, subtract 63 from 75 to find out how much it decreased.
75 - 63 = 12
Divide 12 by 75.
12 / 75 = 0.16
In percents, that is 16%.
He spent 16% less this month.
Hope this helps!
If the first gardener can finish the job in 6 hours, it means that every hour he completes 1/6 of the job.
By the same logic, the second gardener completes 1/7 of the job per hour.
So, if they work together, they complete

of the job per hour.
So, after 42/13 of a hour, they'll complete the job. Since one hour is made of 60 minutes, 42/13 of a hour is

So, it will take them about 194 minutes to finish the job, i.e. about 3 hours and 14 minutes.
Answer:
33beacuse you i have -90×+60=9×6=369-63
Step-by-step explanation:
the change in cost of 145-135.50 = 9.50 for an increase of students from 25 to 30. The ratio of change of cost to change of students = 9.50/5 = 1.9 and becomes the slope coefficient "m" in the formula y= mx + b. y = the total cost, mx becomes the variable cost and b becomes the fixed cost. To find b, use the data point given where the total cost = $135.50 when the students = 25, or 135.50 = 1.9*25 +b. Solving for b yields $ 88. Note that the other data point is where the total cost is $145 for students = 30. Using the new total cost equation shows that 30*1.9+88= 145