NCERT Solutions for Class 4th Maths Chapter 7 Add Up — In-text Questions
Book page 102 Updated on2026-09-19
Q1. Estimate the number of children going on the trip. ____
Answer About 900 children.
438 → about 400
476 → about 500
400 + 500 = about 900
Why it happens: Rounding to the nearest hundred leaves only hundreds to add, and 4 hundreds and 5 hundreds make 9 hundreds.
Tip: An estimate is not the exact answer. It only tells us roughly what to expect, so a silly mistake is easy to spot.
Q2. How many children are going on the trip? 438 + 476
Answer 914 children are going to Mawlynnong.
The working, written in columns.4 H + 3 T + 8 O
4 H + 7 T + 6 O
= 8 H + 10 T + 14 O
14 O = 1 T + 4 O, so the tens become 11 T
10 T = 1 H, so 11 T = 1 H + 1 T
= 9 H + 1 T + 4 O = 914
Why it happens: Every time a column fills up to ten, we bundle those ten and move one to the next column on the left.
Check it yourself: Our estimate was about 900, and 914 is close to it.
Was this helpful? Thanks for the feedback!