Mathematics Quiz For RRB NTPC : 7th January 2020

Q1. The rate of working of A and B are in the ratio of 2:3. The number of days taken by them to finish the work is in the ratio:
(a) 2:3
(b) 4:9
(c) 3:2
(d) 9:4

Q2. The ratio of two positive numbers is 3:4. The sum of their squares is 400. What is the sum of the numbers?
(a) 28
(b) 22
(c) 24
(d) 26

Q3. For what sum will the simple interest at R% for R years will be R?

Q4. Two circles touch each other externally. The distance between their centres is 7 cm. If the radius of one circle is 4 cm, then the radius of the other circle will be
(a) 3 cm
(b) 4 cm
(c) 5.5 cm
(d) 3.5 cm

Q5. Let ∆ABC and ∆ABD be on the same base AB and between the same parallels AB and CD. Then the relation between areas of triangles ∆ABC and ∆ABD will be

Q6. While selling a watch, a shop-keeper gives a discount of 5%. If he gives a discount of 7%, he earns 15 less as profit. The marked price of the watch is
(a) 697.5
(b) 712.5
(c) 750
(d) None of the these

Q7. A student, by mistake, wrote 64 in place of 46 as a number at the time of finding the average of 10 given numbers & got the average as 50. The correct average of the numbers is
(a) 48.2
(b) 48
(c) 48.1
(d) 49

Q8. The successive discount of 15%, 20% and 25% on an article is equivalent to the single discount of
(a) 60%
(b) 47%
(c) 49%
(d) 40%

Q9. If the ratio of cost price and selling price be 10:11, then the profit percentage is
(a) 1%
(b) 10%
(c) 5%
(d) 8%

Q10. Which of the set of three sides can’t form a triangle?
(a) 5 cm, 6 cm, 7 cm
(b) 5 cm, 8 cm, 15 cm
(c) 8 cm, 15 cm, 18 cm
(d) 6 cm, 7 cm, 11 cm