Q1.
Using similar reasoning find out the decimal numbers in the boxes below.
Answer
First find the size of one division on each number line, then count divisions.
First line (8 to 8.1, 10 divisions):
Size of one division = 0.1 ÷ 10 = 0.01
d is at the 1st division → 8 + 0.01 = 8.01
e is at the 5th division → 8 + 5 × 0.01 = 8.05
d is at the 1st division → 8 + 0.01 = 8.01
e is at the 5th division → 8 + 5 × 0.01 = 8.05
Second line (4.3 to 4.8, 10 divisions):
Size of one division = 0.5 ÷ 10 = 0.05
f is at the 1st division → 4.3 + 0.05 = 4.35
g is at the 4th division → 4.3 + 4 × 0.05 = 4.5
h is at the 11th division → 4.3 + 11 × 0.05 = 4.85
f is at the 1st division → 4.3 + 0.05 = 4.35
g is at the 4th division → 4.3 + 4 × 0.05 = 4.5
h is at the 11th division → 4.3 + 11 × 0.05 = 4.85
Why it happens: the marks look identical on both lines, but they stand for different amounts — 0.01 on the first and 0.05 on the second. The value of a division is (labelled gap) ÷ (number of parts), and that must be worked out every time.
Tip: h lies one division beyond the 4.8 mark, so it is 4.8 + 0.05 = 4.85.