2007-06-18 23:06:24 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
let numbers are 3x, 5x and 7x
so 3x+5x+7x = 840
15x=840
x=56
so the numbers are
3 x 56=168
5 x 56=280
7 x 56=392
2007-06-18 23:09:06 · answer #1 · answered by sweet n simple 5 · 8⤊ 1⤋
There may be an easier way to find the answer but.
the numbers in the ratio add up to 15. Divide 840 into 15 equal parts. 3parts:5parts:7parts
840/15 = 56
3*56=168
5*56=280
7*56=392
168+280+392 = 840
2007-06-18 23:22:23 · answer #2 · answered by Paladin01_98 2 · 2⤊ 0⤋
We should write that as
3x + 5x + 7x = 840 (the three numbers will be in the proportion of 3, 5 and 7 as given)
15x = 840
x = 840/15 = 56
So, the numbers are 168, 280 and 392. Their total adds to 840.
2007-06-18 23:25:28 · answer #3 · answered by Swamy 7 · 1⤊ 0⤋
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RE:
three numbers are in the ratio of 3:5:7. if there sum is 840, find the 3 numbers....3+5+7=n?
2015-08-24 05:19:05 · answer #4 · answered by ? 1 · 0⤊ 0⤋
First devide 840 by the sum of the 3 numbers.
840/15= 56.
the first number is 56x3=168
the second is 56x5=280
and the 3rd is 56x7=392
2007-06-18 23:14:15 · answer #5 · answered by Anonymous · 0⤊ 0⤋
this is a very simple math problem.. he he he
formula:
3x + 5x + 7x = 840
Solution
3x + 5x + 7x = 840
15x = 840
x=840/15
x=56
Now you know x, substitute it to the formula
3x + 5x + 7x = 840
3(56)+5(56)+7(56) = 840
168 + 280 + 392 = 840
840 = 840
I hope it will help you!!!!
2007-06-18 23:18:34 · answer #6 · answered by John Jerry J 1 · 0⤊ 2⤋
For the best answers, search on this site https://shorturl.im/aw1ax
paul67337 wrote: "228 divided by 12 is 19. 19 is a common factor in the 3 numbers. go from there and figure out the rest by trial and error." Then just multiply 3, 4 and 5 by 19 and get 54, 76 and 95.
2016-04-10 06:44:14 · answer #7 · answered by Anonymous · 0⤊ 0⤋
can you help me with this ratio.....mike, rachel and joe bought marbles nad share it to the ratio 5:4:3, mike got 15 marbles, calculate the total maount of marbles and how many marbles did rachel get ...please am lost
2014-11-30 09:25:38 · answer #8 · answered by jillian 1 · 0⤊ 0⤋
4320
2013-11-09 08:32:33 · answer #9 · answered by Anonymous · 0⤊ 0⤋