ARITHMETIC ABILITY 6

Thursday, April 29, 2010

Read the questions carefully and pick the correct answer.


1.
Find the 75th term of the series 2, 6, 10, 14 ...
A.
3022
B.
296
C.
298

D.
300
Answer & Explanation
Answer: Option C
Explanation:
75th = a + (n-1)d= 2 + 74 x 4 = 2 + 296= 298

2.
Find the sum of series 2, 4, 6, 8 ... up to 40 terms
A.
1000
B.
960
C.
1640

D.
1650
Answer & Explanation
Answer: Option C
Explanation:
d=2 , n = 40, a = 2Sn = 40/2 (2x2 + 39x2)= 40/2 [ 4 + 78 ]= 40 x 41 = 1640

3.
In how many ways can the face cards be equally divided into two groups
A.
482 ways
B.
350 ways
C.
450 ways
D.
462 ways

Answer & Explanation
Answer: Option D
Explanation:
Total face cards are 12, can be divided into two groups in (12C6 6 C6)/2= 462 ways

4.
5 balls have to be placed in 12 boxes, which are divided into 3 rows of equal number of boxes. The ball must be place in such a way that each row contains at least one ball. In how many ways can this be done.
A.
680

B.
492
C.
486
D.
692
Answer & Explanation
Answer: Option A
Explanation:
Total number of filling and 5 balls in the given 12 boxes - 12 C5 = 792 ways.Choosing the first two rows 5 balls can be 8C5= 56 waysChoosing the last two rows 5 balls can be places in 8C5 = 56 waysTotal number of unfavorable ways = 56 + 56= 112 waysNo. of favorable ways = 792 - 112 = 680 ways.

5.
How many ways are there to race two Dai so that the of the values on the upper force is divisible by 4
A.
11
B.
9

C.
10
D.
12
Answer & Explanation
Answer: Option B
Explanation:
The various arrangement divisible by 4 are(1,3), (2,2), (3,5), (4,4),(5,3),(6,2) and (6,6).There are totally 9 outcomes

6.
In a race of Bulls chances that A will win are 60%, B will win are 20% and that c will win are 30% what is the possibility that one of them will win.
A.
0.428
B.
0.350
C.
0.488

D.
0.398
Answer & Explanation
Answer: Option C
Explanation:
P(A) x P(B1) x P(C1) + P (A) x P (B) x P (C1) + P (A1) x P(B1) x P (C)= 0.6 x 0.8 x 0.7 + 0.4 x 0.2 x 0.7 + 0.4 x 0.8 x 0.3= 0.488

7.
Akash and Anand throw with two dice. If Ashok throws 11 what is Anands chance of throwing a higher number ?
A.
1/36

B.
2/15
C.
1/12
D.
3/20
Answer & Explanation
Answer: Option A
Explanation:
Total number of outcomes of throwing two dice = 6 x 6 = 36Anand must throw 12 which can be done in one way only ( 6 + 6)Thus his chance of throwing 12 is 1/36

8.
From 10 books in how many way can a selection of 5 be made, when one specified book is always included
A.
132 ways
B.
126 ways

C.
148 ways
D.
150 ways
Answer & Explanation
Answer: Option B
Explanation:
Since one book is always included the selection can be in 9C4 ways= 126 ways

9.
Referring to the above question find the number of ways a selection can be made if one book is to be always excluded.
A.
126 ways

B.
150 ways
C.
160 ways
D.
190 ways
Answer & Explanation
Answer: Option A
Explanation:
Since one book is to be always excluded selection can be made in 9C5 ways selection can be made in 9C5 ways.= 126 ways

10.
In the given series select the item that does not fit in the series OMN, RPQ, UTS, YWX
A.
OMN
B.
UTS

C.
RPQ
D.
YWX
Answer & Explanation
Answer: Option B
Explanation:
UTS is does not fit into the series as the order of the alphabets is 312