Think of a real-life example
of where you would round to
one significant figure. This
could be a use for significant
figures in another subject in
school!
Estimate,
Approximate,
Significant,
Decimal, Accuracy
Number
Level of accuracy
19.372
2 d.p.
19.372
1 s.f
0.007519
5 d.p.
0.007519
2 s.f.
46320
2 s.f
153.2617
3 d.p.
4.9043
2 d.p.
23.405
3 s.f.
Rounded answer
Learn the
prime numbers
from 1 – 50
A tower block is
200m high to
the nearest
100m, and 170m
high to the
nearest 10m.
Write down one
possible height
for this tower
block.