1.Average age of a couple is 25 years at the time of marriage. After 3 years, they have a two year old baby. The average age of the family is
(1) 29 years
(2) (19) 1/3 years
(3) (17) 2/3 years
(4) 20 years
2.A shopkeeper allows a discount of 10% on the marked price. How much above cost price must he mark his goods (in per cent) to gain 8%?
(1) 10
(2) 20
(3) 15
(4) 18
3.A gardener has 1000 plants. He wants to plant them in such a way that the number of rows and columns remains same. Then what will be the minimum number of more plants he will need for this?
(1) 35
(2) 25
(3) 24
(4) 34
4.In an alloy of brass, the ratio of copper to zinc is 7 : 4. If 6 kg of zinc be added in 33 kg of such a quality of brass. Then the new ratio of copper to zinc is
(1) 5 : 4
(2) 6 : 5
(3) 7 : 6
(4) 8 : 7
5.Tapas deposited a certain sum of money in a post office at 12% p.a. for 4 years and deposited an equal amount in a bank for 5 years at 15% p.a. If the difference in the interest from the two sources is Rs. 1,890, the sum deposited in each case is
(1) Rs. 5,000
(2) Rs. 9,000
(3) Rs. 7,000
(4) Rs. 8,000
6.A man rides at the rate of 350 metres per minute and stops for 6 minutes to change horses at the end of every sixth kilometer. Then to travel a distance of 84 km, the time taken by the man is
(1) 3 hours 15 minutes
(2) 6 hours 17 minutes
(3) 5 hours 18 minutes
(4) 2 hours 17 minutes
7.Of the two persons, first person can complete a work in 32 days and second person can complete the work in 40 days. Both the persons worked together for 10 days and then the second person leaves. The number of days taken by the first person to finish the balance work is
(1) 16
(2) 14
(3) 21
(4) 7
8.The cost of painting the surface area of a hollow cylinder of length 70 cm and having a diameter 42 cm (negligible thickness) at the rate of 20 paise per sq. cm is
(1) Rs. 3,796
(2) Rs. 3,896
(3) Rs. 3,996
(4) Rs. 3,696
9.Average age of a class is 14.4 years. Average age of boys is 15 years and average age of girls is 14 years. Ratio of number of girls to number of boys is
(1) 2 : 3
(2) 3 : 2
(3) 1 : 3
(4) 1 : 4
10.In an examination, 63% passed in Mathematics, 53% passed in English and 24% failed in both the subjects. If 80 candidates passed in both the subjects, 74 candidates
(1) passed only in Mathematics
(2) failed in both the subjects
(3) passed only in English
(4) failed in Mathematics
Answer Key
1.(2) At the time of marriage,
Husband + Wife = 2×25
= 50 years
Sum of the present ages of husband, wife and child
= 50 + 6 + 2 = 58 years
∴ Required average age = 58/3 => 19 1/3 years
2.(2) C.P. = Rs. 100, Marked price = Rs. x
∴ (x×90)/100 = (100×108)/100
=> 9x/10 = 108
=> x = (108×10)/9=120
i. e. 20% above the cost price.
3.(3) 31 <√1000<32
32×32=1024
∴ Number of extra plants required =l024-1000=24
4.(3) In 33 kg of alloy,
Copper = 7/11 × 33 = 21 kg
Zinc = 4/11 × 33 = 12 kg
On adding 6 kg of zinc,
Required ratio = 21 : (12 + 6)=> 21 : 18 = 7 : 6
5.(3) S.I.
= (principal×Rate×Time)/100
Amount deposited = Rs. x
Interest from post office
= (x×12×4)/100 = Rs. 12x/25
Interest from bank
= (x×15×5)/100=Rs.3x/4
∴ 3x/4-12x/25 = 1890
=> (75x-48x)/100 = 1890
=> 27x/100 = 1890
=> x=(1890×100)/27 = Rs. 7000
6.(3) Speed of horse rider
= 350 metre/minute
= 350/1000 × 60kmph = 21kmph
84÷6=14
i.e. he will change the horse 13 times.
Time taken in changing horses
= 13×6=78 minutes
Time taken in convering 84 km
= 4 hours
Total time = 4 hours + 78 minutes
= 5 hours 18 minutes
7.(2) Work done by first man in
1 day = 1/32
work done by second man in
1 day = 1/40
Work done by both men in 10 days
= 10 (1/32+1/40)
= 10((5+4)/160)=9/16
Remaining work = 1-9/16 = 7/16,
Which will be completed by, first man.
∴ Required time = 7/16 = 32
=14 days
8.(4)
9.(2) Boys = x and girls = y
∴ 14.4 = (15 × x+14 × y)/(x+y)
=>14.4x + 14.4y = 15x + 14y
=>15x-14.4x = 14.4y-14y
=>0.6x = 0.4y
=>y/x=0.6/0.4=3∶2
10.(4)
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