IBPS PO 2017 Quantitative aptitude Practice Quiz 3

1 . Roots of the equation 4x2 – 12x + 9 = 0 are: A.   imaginary and equal B.   rational and equal C.   imaginary and unequal D.   real and imaginary 2 . If log10 2 = 0.3010, then, the value of log10125 will be: A.   2.2000 B.   2.1050 C.   2.0970 D.   3.0107 3 . The value of $\sqrt{1+sin t\over 1-sin t}$ is : A.   tan  t + cos t B.   cos t + sec t C.   sec t + tan t D.   sin t + cos t 4 . The letters of the word WIFE are arranged as in a dictionary. What will be the position of the word WIFE, if the Ist word according to this sequence is EFIW? A.   24 B.   25 C.   26 D.   27 5 . What can be said about the statements I and II? I. log (1 + 2 + 3) = log 1 + log 2 + log 3. II. log (2 + 3 + 4) = log 2 + log 3 + log 4. A.   Both I and II are true B.   I is true but II is false C.   II is true, I is false D.   BOth I and II are false 6 . Meera said to Heera—“My marks are 32% more than yours.” & then Heera replied back to her “My marks are 32% less than yours.” If Heera is telling lies, what should replace the __? A.   20 B.   25 C.   18 D.   24 7 . Sameer is 60% more efficient than Salim and can finish a job in 20 days. How long will Salim take to do it? A.   28 B.   16 C.   36 D.   32 8 . There are 2 trains on parallel tracks, in same direction. The person in faster one passes the slower train in 30 seconds while a person in slower one passes the faster train in 20 seconds. If slow train has length 100 m, which is approximate length of the other? A.   67 m B.   62 m C.   80 m D.   200 m 9 . Direction (Q. 9 & 10): These involve a series, following a rule. One number in the series does not follow the rule. Identify it as ‘x’ and solve the given problems. $Q.$ 2 6 10 20 30 ;$x^2$ +$x\over 2$ = ? A.   144 B.   105 C.   128 D.   150 10 . 5 12 20 32 45 ; If CP of x articles is SP of 20 articles, what is gain %? A.   5% B.   4% C.   2% D.   1%

Answers & Solutions 1 .     Answer : Option B Explanation : Nature of roots is determined by discriminant, D = $b^ 2 – 4ac = (-12)^ 2 – 4 x 4 x 9 = 144 – 144 = 0$ $Since D = 0, or b^ 2 = 4ac$ Roots are equal and rational 2 .     Answer : Option C Explanation : log 125 = log $5^ 3$ = 3 log 5 = 3 log $10\over2$ = 3 (log 10 – log 2) = 3(1 – 0.3010) = 3 (0.6990) = 2.0970. 3 .     Answer : Option D Explanation : $\sqrt{1+sin t\over 1-sin t}$ = $\sqrt{{1+sin t\over 1-sin t}\times {1+sin t\over 1+sin t} }$ = $\sqrt{(1+sin t2)\over (1+sin 2t)*}$ =$\sqrt {({1+sint\over cos t})}2$ = $1\over cost$ +$ sint \over cost$ = sec t + tan t Here, *$1- sin^2T = cos^2t$ 4 .     Answer : Option A Explanation : The $1^ {st}$ word will be: EFIW. Keeping position of E fixed, remaining 3 can be arranged in <3 ways = 3 x 2 = 6 ways. Similarly, we can have another 6 and 6 word with F and I. Now, $19^ {th}$ word = WEFI, $20^ {th}$ = WEIF, $21^ {st}$ = WFEI, $22^ {nd}$ = WFIE, $23^ {rd}$ = WIFE and $24^ {th}$ = WIFE. 5 .     Answer : Option B Explanation : Explanation: - log (ab) = log a + log b Thus, log (1 + 2 + 3) = log 6 and log (1 x 2 x 3) = log 6 But, log (2 + 3 + 4) = log 9 and log (2 x 3 x 4) = log 24 6 .     Answer : Option D Explanation : Required % = $32\over100+32$x 100 = $32\over132$x100 = 24 7 .     Answer : Option D Explanation : 160:100 = 8:5 Time taken = 5:8 = 20:32 8 .     Answer : Option A Explanation : There are 2 trains running parallel. Let relative speed = x m/s Length of slow train = 30x and of fast = 20x i.e. Ratio of length = 3:2 = 1:$2\over3$ since slow train in 100m long, fast train = $2\over3$ x 100 = 67m 9 .     Answer : Option D Explanation : Series is: $n^2 + n$ i.e., $1^2+1,2^2+2,3^2+3,etc$ i.e. 2,6,12,20,........ We should have 12 instead of 10. Thus, x = 12 $x^2+$$x\over2$=$12^2$+$12\over2$ = 150 10 .     Answer : Option A Explanation : The series is: 5 + 7 = 12 + 9 = 21, 21 + 11 = 32, 32 + 13 = 45, etc 20 must be replaced by 121 Thus, x = 21 %Gain = $21-20\over20$x 100 = 5 Also read latest bank recruitment notification Online Test IBPS IBPS PO Notifications IBPS clerk upcoming notifications IBPS PO Online Test