Question

15. A tyre manufacturing company kept a
record of the distance covered before a
tyre needed to be replaced. The table
shows the results of 1000 cases.
Distance
(in km)
Frequency
Less than 4000 to
4000 9000
9001 to
14000
More than
14000
20
210
325
445
If you buy a tyre of this company, what is
the probability that it will need to be
replaced before it has covered 4000 km?​

Answer 1

answer:

Probability that it will need to be replaced before it has covered 4000 km =

1000

20

=0.02

Probability that it will last more than 9000km=

1000

325+445

=

1000

770

=0.77

Probability that it will need to be replaced after it has covered somewhere between 4000 km and 14000 km =

1000

210+325

=

1000

535

=0.535

hope it is right