Answer:A
Step-by-step explanation: 6 divided by 420 = 70
Answer: 40
Step-by-step explanation:
Cody ALONE = 8 hours
Kaitlyn ALONE = 6 hours
Let Joseph ALONE take j hours
Cody ALONE in 1 HOUR = 1/8 of the work Kaitlyn ALONE in 1 hour = 1/6 of the work Joseph ALONE in 1 HOUR = 1/j of the work
Since TOGETHER they take X hours, in 1 hour TOGETHER they complete 1 / X of the work
1/8 + 1/6 + 1/j = 1/X
1/j = 1/X - 1/8 - 1/6 = (24 - 3X - 4X ) /24X = (24 - 7X ) / 24X
j = 24X / ( 24- 7X )
After completing the work value of X will be known , calculate j from the above formula ANSWER
