Search found 26 matches
work done by A= 5000/6
work done by B= 5000/2
Work done together = 5000((1/6)+(1/2))=500(2/3)
Ratio of work done by A = (5000/6)/(500(2/3)) = 3/12 = 1/4
R
- by rajeshvellanki
Sat Apr 21, 2007 2:59 pm- Forum: Problem Solving
- Topic: prep question- work
- Replies: 3
- Views: 2150
- by rajeshvellanki
Sat Apr 21, 2007 2:23 pm- Forum: Problem Solving
- Topic: prep question
- Replies: 6
- Views: 2509
okay i struggled enuf on this to solve, finally it all boils down to this one theorem: An exterior angle of a triangle is equal in measure to the sum of the two non-adjacent interior angles of the triangle 1. since <BDC=<BCD ==> BD=BC 2. now apply the above theorem to triangle BAD ==> <BDC = <BAC + ...
- by rajeshvellanki
Sat Apr 21, 2007 1:46 pm- Forum: Data Sufficiency
- Topic: OG Quant Review: DS, Chapter 5.5, Problem 117 wrong?
- Replies: 16
- Views: 10422
long mehtod:
a1=1;b1=k
a2=b1-a1
==> a2=k-1
b2=b1+a1
==>b2=k+1
a3=b2-a2
a3=(k+1)-(k-1)
==>a3=2
b3=b2+a2
b3=(k+1)+(k-1)
==>b=2k
k now
a4=b3-a3
a4=(2k)-(2)
==>a4=2(k-1)
so ----------------a4=2(k-1)--------------------
- by rajeshvellanki
Sat Apr 21, 2007 8:27 am- Forum: Problem Solving
- Topic: Difficult Math Problem #120 - Sequences
- Replies: 4
- Views: 4364
my bet is on Answer B: here is the explanation for it: A=P(1+(r/n))^(nt) Where P = principal amount (initial investment) r = annual interest rate (as a decimal) n = number of times the interest is compounded per year t = number of years A = amount after time t ==> p=1000, r=r(for now), n=1, t(3)=3 a...
- by rajeshvellanki
Sat Apr 21, 2007 8:10 am- Forum: Problem Solving
- Topic: Difficult Math Problem #121 - Interest
- Replies: 5
- Views: 3322
same explanation but in my way.
since it is an equilateral triangle all arc's are egual in lengh(draw it for more clear picture) since he gave sum of 2 sides=24 ==> each side=12
Perimeter=(3*12)=2*pi*r
2*r=36/pi
==> 2*r=11.34=11(approx)
R
- by rajeshvellanki
Sat Apr 21, 2007 7:30 am- Forum: Problem Solving
- Topic: Geometry question
- Replies: 5
- Views: 2329
Wages same so D1/D2=H1/H2
(X+Y)/(X-Y) = 10/8
(X+Y)/(X-Y) =5/4 ==> X=9Y
Note: Trick in general is just to take ratios when a variable is same.
Speed=distance/time ==> S -> 1/t when distance is same etc..
R
- by rajeshvellanki
Fri Apr 20, 2007 10:24 am- Forum: Problem Solving
- Topic: ps 500 test27 #16
- Replies: 5
- Views: 2033
138-124= 14 gallons increase Given that storm increased the reservoirs to 82% ==> 138=82% of total capapcity X it means it is 18% short from it being a full tank 82%(which is 138)+18%=100% ==>fulltank 138 --> 82% ? --> 18% ( 138*18)/82=30.3 ==> Gallons short of total capcity before storm= 14 + 30.3 ...
- by rajeshvellanki
Fri Apr 20, 2007 9:27 am- Forum: Problem Solving
- Topic: 500 ps test27#13
- Replies: 4
- Views: 2095
- by rajeshvellanki
Fri Apr 20, 2007 9:05 am- Forum: Problem Solving
- Topic: 500 ps test27#14
- Replies: 1
- Views: 1655
good exponential question
x and y are positive integers 5^x-5^y=2^(y-1)5^(x-1) , what is the value of xy?
(A) 48
(B) 36
(C) 24
(D) 18
(E) 12
Answer E
(5^x-5^y)/5^(x-1)=2^(x-1)
5-5^(y-x+1)=2^(y-1)
5=2^(y-1)+5^(y-x+1)
y-x+1=0 for 5=2^(y-1)+5^(y-x+1)
and 2^(y-1)=4 ==> y=3 and x=4
xy=12
answer E
- by rajeshvellanki
Fri Apr 20, 2007 8:41 am- Forum: Problem Solving
- Topic: good exponential question
- Replies: 3
- Views: 2871
a(n)=a1+(n-1)d S=(n/2)(a1+an) d=difference between the consecutive numbers for the first series a=2+4+6+...20 d=2 a1=2 an=20 a(n)=a1+(n-1)d 20=2+(n-1)2 =>n=10 S=(10/2)(2+20) =>S(a)=110 same for b =>n=10 and S=(10/2)(1+19) =>S(b)=100 S(a)-S(b)=110-100=10 You should be able to do most of the math in y...
- by rajeshvellanki
Fri Apr 20, 2007 7:17 am- Forum: Problem Solving
- Topic: there must be a formula for this ?
- Replies: 6
- Views: 3187