1. In a park, there are some cows and some ducks. If total number of heads in the park are 68 and

number of their legs together is 198, then find the number of ducks in the park.

1) 37 2) 47 3) 57 4) 27 5) None of these

Solution: (1).Here, L =198 and H = 68

So, number of cows = (L – 2H) / 2 = (198-2 x 68) / 2

= (198 – 136)/2 = 62/2 = 31

Therefore number of ducks = Number of heads – number of cows

= 68 – 31 = 37

2. Five times of a positive integer is equal to 3 less than twice the square of that number. Find the

number.

1) 3 2) 13 3) 23 4) 33 5) None of these

Solutions : (1). Let the number be x

According to the question ,

5x=2x2 – 3

= 2x2 – 5x – 3 = 0

= (x-3) (2x+1) = 0

X=3, - ½

Thus, the required number is 3.

3. Find the maximum number of trees which can be planted 20 m apart on the two sides of a straight

road 1760 m long.

1) 174 2) 176 3) 180 4) 178 5) None of these

Solution: (4).Number of trees that can be planted on one side of road = 1760/20 + 1 = 88 + 1 = 89

Therefore trees on the both sides = 2 x 89 = 178

4. There are two examination halls P and Q. If 10 students shifted P to Q , then the number of students

will be equal in both the examination halls. If 20 students shifted from Q to P, then the students of P

would be doubled to the students of Q. The number of students would be in P and Q, respective are

1) 60, 40 2) 70,50 3) 80,60 4) 100,80 5) None of these

Solution:( 4). Use the option to solve the sum.

5. In a three-digit number, the digit in the unit’s place is four times the digit in the hundred’s place. If

the digit in the unit’s place and the ten’s place are interchanged, the new number so formed is 18 more

than the original number . If the digit in the hundred’s place is one-third of the digit in the ten’s place,

then what is 25% of the original number?

1) 67 2) 84 3) 137 4) Couldn’t be determined 5) None of these

Solution:(1).Let hundred’s digit = x

Then unit’s digit = 4x and ten’s digit = 3x

Number = 100x + 30x + 4x = 134x

Again, hundred’s digit = x

Ten’s digit = 4x and unit’s digit = 3x

Number = 100x + 40x + 3x = 143x

According to the question,

143x – 134x = 18 = 9x = 18

X=2

Therefore original number = 134x = 134 x 2 = 268

25% of original number = 268 * 25/100 = 67

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