Progression - Online Quiz
Following quiz provides Multiple Choice Questions (MCQs) related to Progression. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.
Answer : D
Explanation
Here a = 14, d = (9 - 14) = -5. ∴ T₁₂ = a + (12 -1) d = a + 11d = 14 + 11 * (-5) = -41.
Answer : C
Explanation
Since 2x, (x+10) and (3x+2) are in A.P. we have (x+10)-2x = (3x+2)-(x+10) ⇒ 10-x =2x-8 ⇒ 3x= 18 ⇒ x= 6
Q 3 - The main term of a number-crunching movement is 6 and its normal distinction is 5. The eleventh term is:
Answer : D
Explanation
Here a =6 and d = 5 T₁₁ = a + (11-1) d = a +10 d = (6+10*5) =56.
Answer : D
Explanation
Here a=45, d =1 and L=115. A+ (n-1) d = 115 ⇒ 45+ (n-1) *1 = 115 (n-1 ) = 70 ⇒ n = 71 Sum = n/2 * (a+L) = 71/2 * (45 +115) = 71/2 *160 = (71 *80) = 5680.
Answer : C
Explanation
Here a = 2 and r = 6/2 =3. 8th term = [a*r (⁸⁻ⁱ)] = ar ⁷ = 2*3⁷ = 2*(2187) = 4374
Q 6 - The third term of a geometrical progression is 4. The result of initial 5 terms is:
Answer : C
Explanation
Let the first term be a and common ratio r. Then ar = 4 Product of 5 first term = a* ar*ar2*ar3 *ar⁴ *= a*r⁴ = (ar2)⁵ = 4⁵
Answer : A
Explanation
This is an infinite G.P in which a =1 and r = 1/2 Sum of infinite G.P. = a/ (1-r) = 1/ (1-1/2) =2
Q 8 - A man heaps logs of wood so that the top layer contains one log and every lower layer has one more than the layer above. In the event that there are 15 layers, the aggregate number of logs will be:
Answer : B
Explanation
Total number of logs = 1+2+3+...+15. This is an A.P. in which a =1, d =1 and n= 15. Sn = n/2(a+1) = 15/2 (1+15) =120
Q 9 - In the event that (12 + 22 + 32+ ......... + x2) = x(x+1) (2x+1)/6, then (12 + 32+ 52 + ...... + 192) =?
Answer : A
Explanation
(12+ 32+52+..........+192) = (12+22+32+42+52+........+182+192) - (22+42+62+.........+182)
= {19*(19+1) (38+1)/6} - (1*22+22*22+22*32+22*42+???. +22*92)
= 2470 -22*{12+22+32+... +92} = 2470 - (4*9*10*19)/6= (2470-1140) = 1330
