If Steven can mix 20 drinks in 5 minutes, Sue can mix 20 drinks in 10 minutes, and Jack can mix 20 drinks in 15 minutes, how much time will it take all 3 of them working together to mix the 20 drinks?
2 minutes and 44 seconds
2 minutes and 58 seconds
3 minutes and 10 seconds
3 minutes and 26 seconds
4 minutes and 15 seconds
EXPLAIN HOW U GOT THE ANSWER PLZ
2007-03-08 03:46:45 · 4 answers · asked by female 1 in Science & Mathematics ➔ Mathematics
In 5 minutes Steven can make 20 drinks
in 1 minute,he can make 20/5 or 4 drinks
In10 minutes sue makes 20 drinks
In 1 minute,he makes 20/10 or 2 drinks
In 15 minutes Jack mixes 20 drinks
In 1 minute he mixes 20/15 or 4/3 drinks
Working together,in 1 minutethey mixes
4+2+4/3 or 22/3 drinks
Therefore for making 20 ddrins,they take
20 divided by 22/3 minutes
=20*3/22 minutes
=2 8/11 minutes
=2 minutes 43.66 seconds
=2 minutes 44 seconds
2007-03-08 04:14:41 · answer #1 · answered by alpha 7 · 0⤊ 0⤋
Add up the rates
20/5 x + 20/10x + 20/15 x= 20
solve for x (time in seconds)
7+(1/3) x = 20
X = 20/ (7+1/3) = 2 minutes and 3/4 = 2 min 45 secs
2007-03-08 04:13:11 · answer #2 · answered by piri82 3 · 0⤊ 0⤋
First find how many they could each do in one minute:
Steven: 20/5 = 4 per minute
Sue: 20/10 = 2 per minute
Jack: 20/15 = 4/3 per minute.
So that's a total of 4+2+4/3 = 7 1/3 per minute
Now divide 20 by 7 1/3 to see how long it would take them added together.
2007-03-08 03:53:46 · answer #3 · answered by hayharbr 7 · 0⤊ 0⤋
is that this user-friendly algebra? purely questioning simply by fact no remember if it somewhat is: 2(6-4d)=25-9d (distribute 2 into the quantity 6-4d) 2X6 - 2X4d = 25 - 9d (2X6=12, 2X4d=8d) 12 - 8d = 25 - 9d (now isolate the variable [d]) (I extra 9d to the two facets and subtracted 12 from the two facets) 12 - 8d = 25 - 9d -12 + 9d = -12 + 9d (now the 12 would be eradicated on the left facet and the 9d would be eradicated on the terrific suited facet) -8d + 9d = 25 - 12 (you may remedy the left facet by using pulling the easy element [d]) d(-8 + 9) = d(a million) = d Now purely remedy the terrific suited facet: 25 - 12 = 13 and you will get: d = 13 As you answer... on your 2nd question: 8 ( 2f - 3 ) = 4 ( 4f - 8 ) back distribute the 8 into the left facet and the 4 to the terrific suited facet: 8x2f - 8x3 = 4x4f - 4x8 8x2 = sixteen 8x3 = 24 4x4 = sixteen 4x8 = 32 => 16f - 24 = 16f - 32 (now subtract 16f and upload 24 to problem facets) 16f - 24 = 16f - 32 -16f + 24 = -16f + 24 (we've eradicated each and every thing from the left facet => left facet = 0) 0 = 16f - 16f - 32 + 24 (element out the easy element [f] from the 1st 2 words) 0 = f ( sixteen - sixteen) - 32 + 24 (sixteen - sixteen = 0) 0 = 0f - 32 + 24 Now in case you typed the equation outstanding, there is not any could desire to proceed given which you will get 0 = -8 and all of us be responsive to that 0 and -8 are 2 diverse numbers, so there is not any answer for this equation. wish this helps, Sean
2016-10-17 21:14:23 · answer #4 · answered by ramayo 4 · 0⤊ 0⤋