Search found 15 matches
in simple way to understand the logic:- t1 = 23 tn = -4 total units to be decreased = 23 + 4 = 27 decrement value= 3 no of times the decrement shall run = 27/3 = 9 {23-3= 20-3= 17-3= 14-3= 11-3= 8-3= 5-3= 2-3= -1-3= -4) tn shall be 9 + 1 = 10 (add 1 becouase of t1 term and rest nine are the no of ti...
- by rairavig
Wed Nov 18, 2015 11:26 pm- Forum: Problem Solving
- Topic: in the arithmetic sequence
- Replies: 7
- Views: 2956
difference between any 1st and 6th consecutive integer is 5
difference between any 2nd and 7th consecutive integer is again 5
so the total difference will be 5*5=25
Ans is 560+25=585
- by rairavig
Wed Jan 29, 2014 8:21 pm- Forum: Problem Solving
- Topic: sum of sequence
- Replies: 6
- Views: 4844
since it ends up at white, which is 3rd bead. we can make the equation as:-
3+5n= Ans
any option with unit didgit as 3 or 8 will b the Ans
i belive the right Ans is (E)
- by rairavig
Wed Jan 29, 2014 8:15 pm- Forum: Problem Solving
- Topic: necklace bead colors
- Replies: 3
- Views: 1577
- by rairavig
Wed Jan 29, 2014 8:09 pm- Forum: Problem Solving
- Topic: I think the answer is 2^5 but the answer says 2^8.
- Replies: 5
- Views: 1879
in above solutions it is clear the the difference between both areas can be calculated as: Difference = 1/2 * (21^2 - 19^2) ..... (A) here i wana advise a general way to calculate the difference between to squares. i.e (n+1)^2 - n^2 = 2n+1 (n+2)^2 - n^2 = 2(2n+2) (n+3)^2 - n^2 = 3(2n+3) ..... so her...
- by rairavig
Tue Nov 05, 2013 11:04 pm- Forum: Problem Solving
- Topic: Difference of areas of 2 TVs
- Replies: 7
- Views: 1478
from above it is clear that in group A we have 17 students and in group B 34 Students. let us assume the total of the age of Group B students is "X" now according to the Question:- X/34 - (X+221 / 51) = 1 Gives X= 544 so the average age is Group B student before merging is 544/34 = 16 (Ans...
- by rairavig
Tue Aug 27, 2013 12:31 am- Forum: Problem Solving
- Topic: Yet another one on averages
- Replies: 3
- Views: 6500
its understood that when ever we make pairs from 6 persons will result 3 teams.
so total possible combinations are 6C2= 15
- by rairavig
Fri Aug 16, 2013 4:00 am- Forum: Problem Solving
- Topic: P n C
- Replies: 5
- Views: 1324
193664000000/130722 = 193664000000/0.130722 x 1000000 = 193664/0.130722 in such cases: take it as =(1/0.13) x 193664 (0.13 ~ 0.130722 if you really wana do this without CalC) = Approx~ 7.7 x 193664 = 14,91,212 (Approx) Actual Ans is- 14,81,495 Difference is only 10,000 which is negligible in such ca...
- by rairavig
Thu Apr 04, 2013 4:24 am- Forum: Problem Solving
- Topic: Suggest some fast calculation techniques
- Replies: 7
- Views: 2619
since 3 students are attending all three classes
student left in each class
math- 14-3=11
English- 10-3=7
PE- 11-3=8
total attendance = 26
student attending only one class= 20
attendance for students attending 2 classes = 6
number of students attending 2 calsses = attendance / classes
= 6/2
= 3
- by rairavig
Wed Apr 03, 2013 10:20 pm- Forum: Problem Solving
- Topic: overlapping set -
- Replies: 7
- Views: 1259
every forth number is divisible bye 4... 400/4= 100 --> now numbers contains 4 as digit 1) from 40-49 we have ten such numbers out of which tthree are divisible by 4 we have already considered above... so we have 7 such numbers in every hundered numbers, here till 400 we will have 7x4= 28 such numbe...
- by rairavig
Wed Apr 03, 2013 10:02 pm- Forum: Problem Solving
- Topic: numbers between 1 and 400
- Replies: 6
- Views: 6033
it is clear now that we have total 720 combinations now it is also understood that every number will be repeated 120 times on each position {Unit place (A),Ten (B),Hundred(C),Thousand(D), Ten Thousand(E), Lacs(F)} for each row total will be the addition of (1x120) + (2x120) + (3x120) + (4x120) + (5x...
- by rairavig
Wed Apr 03, 2013 1:40 am- Forum: Problem Solving
- Topic: Six digit numbers
- Replies: 4
- Views: 1481
Quote: If x>0, then 1 / [√(2x) + √x] = A. 1 / √(3x) B. 1/ 2√(2x) c. 1 / x√2 D. (√2-1) / √x E. (1+√2) / √x Solution: in such problems where you find problem in solving algebra try following method: Let x=1; in such case it should match the equation and we all know √3= 1.732; √2 ...
- by rairavig
Thu Mar 21, 2013 9:38 pm- Forum: Problem Solving
- Topic: Algebra
- Replies: 2
- Views: 1172
assume total work to be done = 8 units done by 6 machines in 8 hours each machine has contibutued in 8 hours = 8 units / 6 = 1.33 Units 5 machines will do in 8 hours 1.33 x 5 = 6.65 units .... (1) total work is 8 units so teh work left to be done = 8 - 6.65 = 1.35 units .....(2) from (1).. 1 hours e...
- by rairavig
Thu Mar 21, 2013 12:39 am- Forum: Problem Solving
- Topic: Hard Work Problem
- Replies: 7
- Views: 3798
http://s22.postimage.org/m5dpuqez1/3x3.jpg Since it is clear from the solutions that shaded and unshaded areas in first two coloums are equal and will cancel each other, we will consider the area present in last coloum, as per question the shaded area is equal to unshaded area:- 3x + 9 = 3 * (6-x) ...
- by rairavig
Thu Mar 21, 2013 12:13 am- Forum: Problem Solving
- Topic: Geometry
- Replies: 5
- Views: 1663
let the revenue for last year is 'x'
projected revenue is x + .2x
actual revenue is x - .25x
the projected revenue was the actual revenue = actual revenue/projected revenue is x + .2x
= x - .25x / x + .2x
= x (1-.25) / x(1+.2)
= 1-.25 / 1+.2
= .75 / 1.2
= .625
in % it would come 62.5%
- by rairavig
Wed Mar 20, 2013 2:28 am- Forum: Problem Solving
- Topic: Percentage problem -1
- Replies: 3
- Views: 1037