BeBop: Math Questions>>>>?
Jack usually mows the lawn in 5 hours . Marliyn can mow the same yard in 3 hours.How much time would it take for them to mow the lawn together?
2nd Question:
The speed of train A is is 20 mph slower than the speed of train B. Train A travels 230 miles in the same time it takes train B to travel 330 miles. Find the speed of train A and train B.
Answers and Views:
Answer by Tomz
I knew how to do these!!!! it’s really bugging me that i can’t remember how! I think you need to set out a table with the points that you know, and gaps for what you dont. try to figure out a connection between parts that you know and try to work them out with respect to the unknown. i hope this helps!
1st :
Jack-> 5 hrs and markiyn-> 3 hrs
hence in 1 hr they wud do 1/5 and 1/3 work respectively and together in 1 hr they wud do
1/5 + 1/3
(5+3)/15
8/15
thus they will complete it in 15/8 hrs together
2nd question:
let a’s speed be x
then b’s -> x+20
230 distance will be covered by a in 230/x time
and 330 distance by b in 330/(x+20) time
time for both is same thus
230/x = 330/(x+20)
solve this
230x+4600 = 330x
4600= 100x
x = 46(a’s speed)
x+20 = 66(b’s speed)
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