Look at several examples of rational numbers in the form \(\frac{p}{q}\) (q ≠ 0), where p and q are integers with no common factors other than 1 and having terminating decimal representations (expansions). Can you guess what property q must satisfy?
Terminating decimal expansion will occur when denominator q of rational number \(\frac{p}{q}\) is either of 2, 4, 5, 8, 10, and so on…
\(\frac{9}{4}\) = 2.25
\(\frac{11}{8}\) = 1.375
\(\frac{27}{5}\) = 5.4
It can be observed that terminating decimal may be obtained in the situation where prime factorisation of the denominator of the given fractions has the power of 2 only or 5 only or both.
Length (in hours) | Number of lamps |
|---|---|
300 − 400 | 14 |
400 − 500 | 56 |
500 − 600 | 60 |
600 − 700 | 86 |
700 − 800 | 74 |
800 − 900 | 62 |
900 − 1000 | 48 |
(i) Represent the given information with the help of a histogram.
(ii) How many lamps have a lifetime of more than 700 hours?
Why was Santosh sent to the local school?