TCS Company Numerical Ability Percentage

Rajesh calculated his average over the last 24 tests and found it to be 76. He finds out that the marks for three tests have been inverted by mistake. The correct marks for these tests are 87, 79 and 98. What is the approximate percentage difference between his actual average and his incorrect average?

Read Solution (Total 5)

zero is right answer:
incorrect value is:78,97,89;
correct value is:87,79,98;
difference b/w correct and incorrect value 87-78=+9,79-97=-18,98-89=+9
so total is= 9+9-18=0;
11 years agoHelpfull: Yes(19) No(4)

percentage will be zero, becoz by changing the digit it does not effect on average value...
11 years agoHelpfull: Yes(4) No(3)
no change
11 years agoHelpfull: Yes(3) No(0)
78+97+89=264 &&&&& 87+79+98=264......then there is not change in sum so avg will remain cons
11 years agoHelpfull: Yes(2) No(0)
0.
(87-78)+(79-97)+(98-89)=0
9 years agoHelpfull: Yes(0) No(0)

TCS Other Question

Joke is faster than Paul, Joke and Paul each walk 24 KM. the sum of their speed is 7 Km per hour. And the sum of times taken by them is 14 hours. Then, Joke speed is
option
a) 3 KM/Hr
b) 4 KM/Hr
c) 5 KM/Hr
d) 7 KM/Hr Platinum is sold in bars of various weights ranging from 13 gms to 593 gms, in 4 gram increments. Each bar is sealed in a opaque box weighing 47 gms. The box used for packaging has no markings on it indicating the weight of the bar inside.
The precious metals merchant selling the boxes has put the packed box into shelves based on the weight. However, to be certain, he weighs the packed box in an equal arms two pan balance, and a set of weights (which is common for all the box, and which he considers as standards weights) Each of these weighs an integral no.of grams and have their weight marked on them. The merchant, superstitious man always places the packet box of platinum in the left pan, and places the appropriate weights in the left pan or the right pan or both until the balance is achieved. This suffices to tell him the weight of the packed bar.
What is the minimum number of standard weights the merchant must have to be able to accurately determine the weight of the packed boxes.
option
a) 3
b) 8
c) 5
d) 6