Question Details

Directions (42-43):Given below three series I, II & III and each series has a wrong number . The number that should come in place of wrong number in series I, II & III is a, b & c respectively .


I. 5, 6, 8, 14, 38, 168, 878, 5918

II. 32, 544, 593, 809, 832, 898, 907

III. 18, 38, 124, 500, 2504, 15028, 105200


If m2 = a + 98 , then which of the following statement/s is or are true.

(A) ( b m + 0.5 ) = resultant is an integer.

(B) 10m = c

(C) m + b 42 18 c

Options

A

Only (A) and (C)

B

Only (B) and (C)

C

Only (A) and (B)

D

All three

Show Answer

Correct Answer :

Option A

Only (A) and (C)

Only (A) and (C)

Solution :

To find the correct statements, we first need to identify the wrong number in each series and determine the correct values for a, b, and c.

Step 1: Analyze Series I
The given series is: 5, 6, 8, 14, 38, 168, 878, 5918
Let's find the difference between consecutive terms:
6-5=1=1!
8-6=2=2!
14-8=6=3!
38-14=24=4!
Following this factorial difference pattern, the next difference should be 5!=120.
So, the term after 38 should be:
38+120=158
Let's check the subsequent terms using this corrected value:
158+6!=158+720=878
878+7!=878+5040=5918
Since these match the rest of the series, the wrong number is 168, and the correct number is a = 158.

Step 2: Analyze Series II
The given series is: 32, 544, 593, 809, 832, 898, 907
Let's examine the differences:
544-32=512=83
593-544=49=72
809-593=216=63
The pattern of differences is alternating cubes and squares of decreasing numbers: 83,72,63,52,43,32.
So, the next difference should be 52=25.
The term after 809 should be:
809+25=834
Let's verify with the remaining terms:
834+43=834+64=898
898+32=898+9=907
Since these match, the wrong number is 832, and the correct number is b = 834.

Step 3: Analyze Series III
The given series is: 18, 38, 124, 500, 2504, 15028, 105200
Let's analyze the relationship between consecutive terms starting from the later terms:
15028×7+4=105196+4=105200
2504×6+4=15024+4=15028
500×5+4=2500+4=2504
124×4+4=496+4=500
The pattern is Tn=Tn-1×n+4.
Working backwards to the start of the series:
The second term should be:
18×2+4=40
Checking if 40 gives the next term:
40×3+4=124
This is correct. Thus, the wrong number is 38, and the correct number is c = 40.

Step 4: Find the value of m
We are given:
m2=a+98
Substituting a = 158:
m2=158+98=256=16
Since m2=16, m can be 4 or -4.

Step 5: Test the statements for both possible values of m

Case 1: If m = 4
• Statement (A):
bm+0.5=8344+0.5=208.5+0.5=209 (which is an integer) - True
• Statement (B):
10m=10×4=40=c - True
• Statement (C):
m+b-4218=4+834-4218=4+79218=4+44=48
Since 4840 (which is c) - True

Case 2: If m = -4
• Statement (A):
bm+0.5=834-4+0.5=-208.5+0.5=-208 (which is an integer) - True
• Statement (B):
10m=10×(-4)=-4040 - False
• Statement (C):
m+b-4218=-4+44=40
Since 4040 (which is c) - True

Because Statement (B) is not true when m=-4, only Statements (A) and (C) are true under all mathematically valid conditions for m.

Unlock Our Free Library

Access expert-curated educational resources and study materials—completely free.

Discover more resources

You may also like

Mock Tests

View All
  • CLAT
  • intermediate
  • 2 hours
  • current affairs, general knowledge, legal reasoning, logical reasoning, quant

  • CLAT
  • intermediate
  • 2 hours
  • current affairs, english, general knowledge, legal reasoning, logical reasoning, quant

Ask AI Tutor
5 left
Q1 View Question & Options
AI Tutor is solving this question...
Reading question context & options...