Answer:
4 hours
Step-by-step explanation:
For three visits, the electrician earned $40 × 3 = $120 in "per-visit" charges. For working x hours, he earned 20x in "per-hour" charges. The total of these came to 50x:
120 +20x = 50x
120 = 30x . . . . . . . . subtract 20x
4 = x . . . . . . . . . . . . . divide by 30
The electrician worked 4 hours that day.
Answer:
28 students
Step-by-step explanation:
Let number of students in cooking club = x
Number of students in fencing club = 1/5 x
Number of students in chess club = 2(1/5)x
Since, There are 42 more students in the cooking club than in the chess club
Then ;
Number of students in chess club = Number of students in cooking club - 42
2(1/5)x = x - 42
(2/5)x - x = - 42
(2/5)x - x = - 42
-0.6x = - 42
x = 42 / 0.6
x = 70
Hence, number of students in chess club :
(2/5) * 70 = 28
I can’t type it out but the equation is Pi(radius)^2