NCERT Solutions for Class 5th Maths Chapter 12 Three things to measure with a seconds hand — Let Us Find
Book page 158 Updated on2026-09-19
Q1.
Find out the number of times you can skip the rope in 10 seconds.
Answer
You have to measure this one yourself. Here is exactly how.
Fix the 10 seconds. A friend watches the seconds hand. Ten seconds is two big steps of the seconds hand — for example from 12 to 2.
Get ready with the rope behind your feet before the timing starts.
On start, skip steadily and count each time the rope passes under your feet.
On stop, write down your count.
Do it three times and take the best count. Practice makes the number go up.
Sample answer: I skipped 18 times in 10 seconds.
18 skips in 10 seconds In 60 seconds (1 minute) that would be about 6 × 18 = 108 skips
Why we multiply by 6: One minute is 60 seconds, and 60 ÷ 10 = 6. So a minute holds six lots of 10 seconds. Six lots of 18 skips is 108 skips — as long as you do not get tired, which you probably will.
Q2.
How long does it take you to write the word FRIEND?
Answer
Time yourself with a clock that has a seconds hand.
Keep your pencil and notebook ready, page open.
A friend says start when the seconds hand touches 12.
Write FRIEND in your normal handwriting — not scribbled, not extra neat.
Say done. Your friend reads how many small marks the seconds hand has moved.
Sample answer: I took 5 seconds to write FRIEND in capital letters.
FRIEND has 6 letters 6 letters in 5 seconds → a little under 1 second per letter
Try This: Now write FRIEND ten times and time that. Did it take ten times as long, or less? Most children speed up after the first two or three tries.
Q3.
How long does it take you to run 100m?
Answer
Measure this on your school ground, with a friend or your teacher holding the watch.
Mark the 100 m with a starting line and a finishing line. Ask your teacher to help measure it.
The timekeeper stands at the finish line, watching the seconds hand.
The timekeeper notes the second at which you start.
The timekeeper notes the second at which you cross the finish line.
Subtract to get your time.
Sample answer: I started when the seconds hand was on 12 and finished when it had moved 21 small marks. So I took 21 seconds to run 100 m.
Why we time the runner, not the distance: The distance is fixed at 100 m for everybody. So the only thing that can change is the time. Whoever takes the fewest seconds is the fastest — the same rule that decided the 200 m walking race on page 157.
Did you know? The fastest men in the world run 100 m in under 10 seconds. That is faster than most people can count to ten.