Day 179: CDS Maths

5 questions. Try each one first, then open its answer.

Question 1
Sequence and Series. Asked once: CDS 1 2018 (same type asked 3 times) See all 3 of this type
52 $The arithmetic mean of two numbers is 10 and their geometric mean is 8. What are the two numbers?$
Tap an option to check your answer.
Question 2
Sequence and Series. Asked once: CDS 2 2016 (same type asked 3 times) See all 3 of this type
25 $\sqrt{1 + \frac{1}{1^2} + \frac{1}{2^2}} + \sqrt{1 + \frac{1}{2^2} + \frac{1}{3^2}} + \ldots + \sqrt{1 + \frac{1}{2007^2} + \frac{1}{2008^2}}$
Tap an option to check your answer.
Question 3
Statistics. Asked once: CDS 2 2016 (same type asked 3 times) See all 3 of this type
88 $20.5$
Tap an option to check your answer.
Question 4
Time, Speed and Distance. Asked once: CDS 1 2017 (same type asked 3 times) See all 3 of this type
31 $A passenger train departs from Delhi at 6 p.m. for Mumbai. At 9 p.m., an express train, whose average speed exceeds that of the passenger train by 15 km/hour leaves Mumbai for Delhi. Two trains meet each other mid-route. At what time do they meet, given that the distance between the cities is 1080 km ?$
Tap an option to check your answer.
Question 5
Algebraic Identities and Simplification. Asked once: CDS 1 2020 (same type asked 3 times) See all 3 of this type
17 $x^{2} + 9y^{2} = 6xy$
Tap an option to check your answer.

Question 1