Mathematics Questions for CDS & CAPF: 27th October

Dear Students, Defence Adda is providing you all with this quiz on Mathematics questions for CDS, AFCAT, CAPF and other Defence Examinations. The questions asked in Mathematics Section of most of the defence examinations are based on the topics from Mathematics of Class 11th and 12th. The questions asked in this section are complex and comparatively difficult but once attempted with high accuracy, can fetch you full marks in this section. Also, practice on a daily basis helps one dive into the core concepts of a subject and thus, help her perform to the best of her ability in the real examinations. So, attempt the daily quizzes being provided by Defence Adda and score to the maximum in the Mathematics Section of all sorts of defence examinations.

Q1. The compound interest on a certain sum of money for 2 years at 10% per annum is Rs. 420. Find the simple interest at the same rate and for the same time.
(a) Rs. 400
(b) Rs. 500
(c) Rs. 450
(d) Rs. 550

Q2. Manoj marked up an article for Rs 15000. Had he offered a discount of 10% on the marked price, he would have earned a profit of 8%. What is the Cost price?
(a) Rs. 12,500
(b) Rs. 13,500
(c) Rs. 12,250
(d) Rs. 13,250

Q3. A shopkeeper mixed two verities of rice at Rs. 20/kg and Rs. 30/kg in the ratio 2 : 3 and sell the mixture at 10% profit. Find the price per kg at which he sold the mixture?
(a) Rs. 26
(b) Rs. 28.8
(c) Rs. 28
(d) Rs. 28.6

Q4. Two pipes A and B can fill a tank in 36 hours and 45 hours respectively. If both the pipes are opened simultaneously, how much time will be taken to fill the tank?
(a) 20 hours
(b) 30 hours
(c) 15 hours
(d) 25 hours

Q7. If the length of a rectangular plot of land is increased by 5% and the breadth decreased by 10% by how much will its area change?
(a) Increase by 5.5%
(b) Decrease by 5.5%
(c) Decrease by 0.55%
(d) No change

Q8. A quadrilateral ABCD circumscribes a circle and AB = 6cm, CD = 5 cm and AD = 7 cm. The length of the sides BC is
(a) 6 cm
(b) 4 cm
(c) 5 cm
(d) 3 cm

Q9.  A cone, a hemisphere and a cylinder stand on equal bases and have the same height. The ratio of their respective volumes is:
(a) 1 : 2 : 3
(b)2 : 1 : 3
(c) 1 : 3 : 2
(d)3 : 1 : 2

Q10. In a ∆ABC,  BC=9 cm,AC=40 cm and AB = 41 cm. If bisector of angle A meets side BC at D then ratio of area of ∆ABD ad ∆ABC is -
(a) 40 : 41
(b) 9 : 40
(c) 9 : 41
(d) 41 : 81

SOLUTIONS

S1. Ans.(a)
Sol.
C.I= 10+10+(10*10)/100
= 21%
21%=R.s 420
S.I(20%)= Rs.400

S2. Ans.(a)
Sol.
M.P=Rs15000
SP after 10% discount= 15000-10%of15000= 15000-1500=Rs13500
Profit on SP= 8%
CP= 13500⁄108 ×100=Rs. 12500

S3. Ans (d):
Sol.
CP of mixture = (20*2+30*3)⁄2+3 = 26
SP of the mixture = 1.1×26=28.6

S4.Ans (a):
Sol.
Part filled by A in 1 hour = (1/36);
Part filled by B in 1 hour = (1/45);
Part filled by (A + B) In 1 hour =(1/36)+(1/45)=(9/180)=(1/20)
Hence, both the pipes together will fill the tank in 20 hours.

S7. Ans (b)
Sol.
Required change in area

= 5-10 -  (5×10)/100= -5.5%
Negative sign shows decrease.