Home › RRB NTPC › Quantitative Aptitude › Time, Speed and Distance › Zaheeda doubles her speed on the same route. The…
Zaheeda doubles her speed on the same route. The time she takes:
ADoubles
BFalls to one third
CFalls to one half
DIs unchanged
Answer & Solution
Correct answer: C. Falls to one half
1. The route is the same, so the distance is fixed.
2. Speed and time are therefore in inverse proportion.
3. As Zaheeda doubles her speed by running, the time reduces to half.
4. Increasing her speed threefold by cycling would cut the time to one third.
5. So the factor by which speed rises is exactly the factor by which time falls.
_Source: NCERT Class 8 Maths, Ch 11 'Direct and Inverse Proportions', S11.3 Inverse Proportion_
Related questions
The first step in a distance, rate and time problem, after reading it, is to:Hamilton drove 40 mph in the city and in the desert he drove:Hamilton's rate in the desert was how many times his rate in the city?Hamilton left home at 2:00 pm and entered the desert at 4:30 pm, so he drove in the city fHamilton's trip to Las Vegas from Orange County covers:Katie Mae's home is how far from her school?If Katie Mae walks at 3 mph and bikes 3 mph faster, her biking speed is:Katie Mae is 3 mph faster on her bike than on foot. Her walking speed is: