EN हिं

NCERT Solutions Ganita Prakash Chapter 10 Comparing numbers using floors — Figure it Out

Book page 247 Updated on2026-09-05

Q1.
Compare the following numbers using the Building of Fun and fill in the boxes with < or >. a. – 2 ☐ + 5 b. – 5 ☐ + 4 c. – 5 ☐ – 3 d. + 6 ☐ – 6 e. 0 ☐ – 4 f. 0 ☐ + 4
Answer
ComparisonReason from the building
a.– 2 < + 5Video Games is below the Sports Centre
b.– 5 < + 4The Dinosaur floor is below Ice Cream
c.– 5 < – 3Floor – 5 is below Floor – 3
d.+ 6 > – 6Six floors up is above six floors down
e.0 > – 4The ground floor is above every basement floor
f.0 < + 4The ground floor is below every floor above it
Two rules you can now say aloud: every negative number is less than 0, and every positive number is greater than 0. So any negative number is smaller than any positive number, no matter how big its digits look.
Q2.
Imagine the Building of Fun with more floors. Compare the numbers and fill in the boxes with < or >: a. – 10 ☐ – 12 b. + 17 ☐ – 10 c. 0 ☐ – 20 d. + 9 ☐ – 9 e. – 25 ☐ – 7 f. + 15 ☐ – 17
Answer
a. – 10 > – 12     b. + 17 > – 10     c. 0 > – 20
d. + 9 > – 9     e. – 25 < – 7     f. + 15 > – 17
  • a. Floor – 10 is only 10 floors down, Floor – 12 is 12 floors down — so – 12 is lower, and – 10 is greater.
  • b, d, f. A positive floor is always above a negative floor.
  • c. The ground floor is above the 20th basement.
  • e. Floor – 25 is much deeper than Floor – 7, so – 25 is the smaller number.
Tip: For two negative numbers, the one with the larger digits is smaller. Compare the digits, then flip your answer.
Q3.
If Floor A = – 12, Floor D = – 1 and Floor E = + 1 in the building shown on the right as a line, find the numbers of Floors B, C, F, G, and H.
Answer

The ticks on the line are one floor apart, so simply count. Between D (– 1) and E (+ 1) there is one unmarked tick — that is Floor 0, which fixes the scale.

H+ 11 G+ 6 F+ 2 E+ 1 0 D– 1 C– 6 B– 9 A– 12
The building drawn as a line. The three given floors A = – 12, D = – 1 and E = + 1 fix the scale; the floors found are shown in red.
B is 3 ticks above A: – 12 + 3 = – 9
C is 3 ticks above B: – 9 + 3 = – 6
F is 1 tick above E: + 1 + 1 = + 2
G is 4 ticks above F: + 2 + 4 = + 6
H is 5 ticks above G: + 6 + 5 = + 11

Answer: B = – 9, C = – 6, F = + 2, G = + 6, H = + 11.

Check it yourself: count the ticks from D (– 1) straight up to H — there are 12 of them, and – 1 + 12 = + 11. ✔
Q4.
Mark the following floors of the building shown on the right. a. – 7 b. – 4 c. + 3 d. – 10
Answer

Count ticks from a floor you already know. Each tick is one floor.

  • – 7 — two ticks above B (– 9), that is one tick below C (– 6).
  • – 4 — two ticks above C (– 6), or three ticks below D (– 1).
  • + 3 — one tick above F (+ 2).
  • – 10 — two ticks above A (– 12), or one tick below B (– 9).
0 D = – 1 A = – 12 c. + 3 b. – 4 a. – 7 d. – 10
The four floors marked on the building line: + 3 above the ground, and – 4, – 7 and – 10 below it.
Order from lowest to highest: – 10 < – 7 < – 4 < + 3
Was this helpful? Report an error