Here actually we use to find the ratio is the the ratio between c:a
Beacause already a:b & b:c are given
to find c:a
here we got 3:5 by
by taking the last digit in the ratio a:b 2:3 we took 3
by taking the first digit in the ratio b:c 5:8 we took 5
then mulltiply the
ratio numbers in b:c with 3/5 then we will get
Mukesh said:
(Fri, Dec 10, 2010 07:33:24 AM)
How do we take 3:5 and why.
Explain how 8*3/5 came ? and why.
Kalpa said:
(Sun, Dec 26, 2010 10:57:43 AM)
Let 3 number are X,Y,Z
given X+Y+Z=98
X:Y::2:3 Y:Z::5:8
=> X/Y=2/3 =>Y/Z=5/8
=> X=2Y/3 =>Z=8Y/5
so,X+y+z=98
=>2Y/3+y+8Y/5=98
=>(10Y+15Y=24Y)/15=98
=>Y=1470/49
=>Y=30
so,2nd no. is 30.
Aparna said:
(Sun, Dec 26, 2010 03:38:35 PM)
Here's the simple method
Solve it by using scaling method
A B C
2 3
5 8
find the lcm of middle term,i:e 5 and 3.its 15
in order to get 15,look at upper part,3 is reqd. to be mutiplied by 5,and 5 by 3 in lower part
A B C
2 3(5)
5(3) 8
ans:
2*5:3*5:8*3
10:15:24
Karthik said:
(Sat, Jan 8, 2011 01:03:15 PM)
Hi aparn.
Its very easy to understand. Thank you.
Daksh said:
(Thu, Jan 13, 2011 05:34:01 AM)
Explain how B=(98*15/49) ?
Aparna said:
(Sun, Jan 30, 2011 03:00:52 PM)
Look at the ratio:
10:15:24
here B's part is 15
and this 15 is out of 49(10+15+24)
just mutiply (15/49) by 98
to get the actual value of B
Abhishek said:
(Fri, Feb 25, 2011 05:58:52 AM)
Now,the most easiest and trick method can be:
See, 2:3 and 5:8 are the ratios of First:Second and Second:Third,
So,the Second No. should be a multiple of 3 and 5.So,3*5=15,
Now, choose among the choices of answers,the correct one is [B]30.
30 is the multiple of 15(both 3 and 5)....
Babu said:
(Fri, Mar 11, 2011 04:43:00 AM)
Excellent Kalpa
Ranjani said:
(Fri, Mar 25, 2011 08:39:36 AM)
Nice aparna.
Akila said:
(Thu, Apr 28, 2011 03:24:14 AM)
Thanks kalpa! I understood easily.
Ashok Sarkar said:
(Sat, May 7, 2011 09:10:14 AM)
Thanks kalpa it's very easy to understand
Alisha said:
(Wed, Jun 22, 2011 11:41:04 PM)
a+b+c=98
a/b=2/3 and b/c=5/8 and hence
a=2b/3 and c=8b/5
so,
2b/3+8b/5+b=98
34b+15b=98*15
49b=98*15
and finally, b=(98*15)/49=30
Sum of numbers Ax+Bx+Cx=98->1
Ratio of first to second 2:3
second to third 5:8
the ratio A:B::C:D=2:3::5:8
find the ratio A:B:C
i.e A:B:C=2:3::(5*(3/5)):(8*(3/5)).
new ratio is 2:3::3:24/5
A:B:C=2:3:24/5
A:B:c=10:15:24
from 1 we get
10x+15x+24x=98
x=2
second number =15*2=30.
Avijeet said:
(Mon, Sep 5, 2011 07:50:55 PM)
Thanks alisha.
You used awesome shortcut:).
Vicky Singh said:
(Tue, Sep 6, 2011 05:47:21 PM)
Thanks kalpa for solve such easy method to this question.
Amit said:
(Mon, Sep 12, 2011 12:41:45 PM)
Hey thanks kalpa, its very easy to understand.
Sweet said:
(Sat, Nov 5, 2011 03:05:02 PM)
Let a's amount= z
so b's amount=1210-z
now (4/15)z=(2/5)x(1210-z)
=>
(4/15)z=484-2/5z
=>
(4/15)z+(2/5)z=484
=>
by taking l.c.m (10/15)z=484
=> 10z=7260
=>
z=726
So a's amount=z=726
and b's amount=1210-726=484 ans.
Ankur Saxena said:
(Wed, Nov 30, 2011 01:13:38 PM)
a/b=2/3,b/c=5/8
a+b+c=98
2b/3+b+8b/5=98
b=30
Murali said:
(Thu, Dec 8, 2011 08:06:58 PM)
If a:b:c=2:3:5 then the ratio of (b+c)/4:(c+a)/4:(a+b)/4 is?
Can any one give answer for this....
Rishikesh said:
(Mon, Jan 30, 2012 08:59:31 AM)
Thanks alisha.
Deepi said:
(Sat, Feb 4, 2012 12:24:52 PM)
Hi Guys,
I have a shortcut method like this kind of problems see this
a:b:c can be calculated easily from a:b and b:c just multiply as shown below
a:b
b:c
-------
a*b:b*b:b*c
So from the problem 2:3 is a:b and 5:8 is b:c
2:3
5:8
-------
2*5:3*5:3*8
answer is 10:15:24
Here given is sum of three number is 98.
that is 10+15+24=49
49=98
15=? => (15*98)/49 = 30.
Nisha said:
(Sat, Feb 4, 2012 11:44:49 PM)
Thanks kalpa.
Deepi said:
(Sun, Feb 5, 2012 04:43:10 PM)
SEE This carefully
a:b1
- b2:c
-----------
a*b2:b1*b2:b1*c=a:b:c
A : B : C = 2 : 3 :