EASY
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The heights of five runners are 160 cm, 137 cm, 149 cm, 153 cm and 161 cm respectively. Find the mean height per runner.

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Important Questions on Progression and Series

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Let a1,a2,..a10 be a G.P. If a3a1=25, then a9a5  equals:
 
HARD

If m is the A.M. of two distinct real numbers I and n I, n>1  and G1, G2 and G3 are three geometric means between I and n, then G14+2G24+G34 equals

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The product of three consecutive terms of a G.P. is 512. If 4 is added to each of the first and the second of these terms, the three terms now form an A.P., then the sum of the original three terms of the given G.P. is :
MEDIUM
The sum of first 20 terms of the sequence 0.7, 0.77, 0.777, ......, is :
MEDIUM
If y=cos2x+sec2x, where 0x<π2, then which one of the following is correct?
HARD
The number of real solutions of the equation sin-1i=1xi+1-xi=1x2i=π2-cos-1i=1 -x2i-i=1-xi lying in the interval -12,12 is____.

(Here, the inverse trigonometric functions sin-1x & cos-1x assume values in -π2,π2 & 0,π

respectively.)
HARD
Let bi>1 for i=1, 2,.,101. Suppose logeb1,logeb2,..,logeb101 are in Arithmetic Progression (A.P.) with the common difference loge2.  Suppose a1, a2,.,a101 are in A.P. such that a1=b1 and a51=b51. If t=b1+b2++b51 and s=a1+a2++a51, then
MEDIUM
Let C0 be a circle of radius 1. For n1, let Cn be a circle whose area equals the area of a square inscribed in Cn-1. Then u=0areaCi equals,
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The arithmetic mean and the geometric mean of two positive numbers p and q(p>q) are A and G respectively. Which one of the following is correct?
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Collect all the sequence of the five consecutive integers such that their product is equal to one of the least integer. Let X be the collection of all possible such sequences. Let P be the smallest integer and Q be the largest integer in the sequences.

What is the arithmetic mean of P and Q?

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The sum of the 3rd and the 4th terms of a G.P. is 60 and the product of its first three terms is 1000. If the first term of this G.P. is positive, then its 7th term is:
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For  x>0, what is the minimum value of x+x+22x ?
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The quotient when 1+x2+x4+...+x34 is divided by 1+x+x2+...+x17 is
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Let a, b and c be the 7th, 11th and 13th terms respectively of a non-constant A.P. If these are also the three consecutive terms of a G.P., then ac is equal to:
HARD

Let S1 be the sum of areas of the squares whose sides are parallel to coordinate axes. Let S2 be the sum of areas of the slanted squares as shown in the figure. Then S1/S2 is

Question Image

MEDIUM
If three distinct numbers a, b, c are in G.P. and the equations ax2+2bx+c=0 and dx2+2ex+f=0 have a common root, then which one of the following statements is correct?
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If the 2nd, 5th and 9th terms of a non-constant arithmetic progression are in geometric progression, then the common ratio of this geometric progression is
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What is the minimum value of cos3θ+sec3θ where 0oθ<90o?
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The harmonic mean and the geometric mean of two numbers are 10 and 12 respectively. What is their arithmetic mean?
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The geometric mean of x and y is 6 and the geometric mean of x, y and z is also 6. Then the value of z is: