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2, B

1, One of the following is different from the other, which one? 263, 284,344, 362, 482,551 2, in mathematics examination the average for the entire class was 80 marks .if 10% of the students scored 95 and 20% scored 90, then what was the average mark of the remaining students of the class ? A, 70 B, 75 C, 80 D, 72

1, two dice are tossed at the same time, then what is the probability that the sum of the numbers appear together is prime? A, 1/9 B, 5/12 C, 7/12 D, 5/18 2, the lateral edge of a regular tetrahedron is 4cm, then find Surface area and volume. 1,B 3, the diagonal of a rectangle is radical 34cm, if the area of the rectangle is 15 sq.cm, then its perimeter = ------ cm? 3, let l and w be the dimensions of the rectangle l2 + w2 = 34 -------(1) from area lw = 15 ------(2) (l + w)2 = l2 + 2lw +w2 = 34 + 30 = 64 l + w = 8 -----(3) perimeter = 2(l +w) = 16 4, three persons can complete a given task in three hours if they work together . If the second person twice as fast as the first and the third person twice as fast as the second, then how much time they took to finish the work alone? 4, let x be the time required by the first person 1/x + 2/x + 4/x = 1/3 7/x = 1/3 x = 21hr first person Second person = 21/2hr Third person = 21/4hr

44%

1, 31.1% 2,28

If each sides of a square increased by 20%, then the % change in area = ? A, 40% B, 42% C, 43% D, 44%

1, 5/9 part of the population in the village are males .if 30% of the female are maried , then find the % of unmarried female in the village . 2, which one of the following is not found in the sequence ? 7, 28, 63, 124, 215, 342,...

The average age of a group of men is increase by 5 years when a person aged of 18 years replaced by a new person of aged 38 years . How many men are there in the group? Let m be the sum of the age of during 18 years. n be the no. of men x be the original mean m/n = x -------(1) (m + 20)/n = x + 5 m/n + 20/n = x + 5 -----(2) x + 20/n = x + 5 20/n = 5 5n = 20 n = 4

Answer : 1,A,2A,3A,4A,5A,6C,7C,8B,9C,10A,11D, 12,A,13D replace +16 by +4 14B,15,C16,B replace -3 by -5 17,A, 18,B

1, the mean of 10 observation is 10. If all the observation increased by 20%, then the new mean = ---? 2, the sum of highest and lowest values is 80. and coefficient of range is 0.625, then the difference between highest and lowest values is ---? 3, which one of the following is unit free? A, range B, CV C, Standard deviation D, AM 4, If the value of mode is 14 and AM is 5, then median = ----? A, 12 B, 18 C, 8 D, 14 ( assume the distribution is moderately skewed )

The angle of depression from an airplane to the point on the ground is 30 degree and after travelling 200km the angle of depression of the same point is 60 degree , then find i, the height of the plane above the ground. ii, the distance traveled by the plane after angle of depression of 60 degree so the plane come directly above the point?

Volume of cone = volume of sphere (phi.r2.h)/3 = 4/3(phi.r3).n (20)(20)(10) = 4(8).n n = 4000/32 n = 125, n = number of spheres

A solid metallic cone of height 10cm and base radius of the base 20cm is melted to make spherical balls each 4cm in diameter . How many such balls can be made?

1, n(S) = 14C2 = 91 n(E) = 6C2 + 8C2 = 15 + 28 = 43 P(E) = 43/91 2, (x + x+1 + x+2 +x+3 + x +4 + x + 5+ x +6)/7 = 20 7x + 21 = 140 7x = 119 x = 17 largest =:17 + 6 = 23

1,A bag contain 6 red and 8 black balls. If two balls are drawn at a time then what is the probability that they are of the same colors ? 2, the average of 7 consquetive natural numbers is 20, then what is the largest number ?

1, The largest three digit number when divided by 6, 9, 12 leaves 3 as remainder = ? Ans find lcm of 6, 9, 12 = 36 Divide 999 to 36 which is the largest three digit no. Remainder = 27 999 - 27 =972 The req. No. = 972 - 3 = 969 2, the difference of two numbers is 1365. When the larger number is divided by the smaller the quotient is 6 and the remainder is 15, then find the smaller number. Ans: let x and y be the two numbers y = x + 1365 --------- (1) y = 6x + 15 ------------(2) from 1 and 2 6x + 15 = x + 1365 5x = 1350 x = 1350/5 = 270 3, in the sequence 10, 15 ,22, x, 42, 55,70, ..., x = ?A, 30 B,28 C, 31 D,29 4, in the sequence 3, 12, x, 48, 75, ..., x = ?A,27 B, 21 C, 15 D,36 3, the difference is A.P, there fore it is 9 + 22 = 31 4, 12 + 15 = 27 5, let x, y be an elements of real numbers if x - y = 3 and x2 + y2 = 29, then xy = ? Ans: (x - y)2 = x2 - 2xy + y2 2xy = x2 + y2 - (x - y)2 2xy = 29 - 9 2xy = 20 xy = 10 6, the volume of a cube is 729 cm3 , then find surface area, lateral surface area and length of diagonal . Ans: v = x3 x = cube root of 729 x = 9cm TSA = 6x2 = 6*81 = 486 diagonal = (rad3)x = 9rad3 LA = 4x2 = 4*81 = 324 7, three un biased coins are tossed . What is the probability of getting at most two heads ? Ans: n(S) = 2 raised to 3 = 8 n(E) = 3C0 + 3C1 + 3C2 = 1 + 3 + 3 = 7 p(E) = 7/8 P(E) = 1 - p(3C3) 1 - 1/8 = 7/8 by compliment law.