B) A factor of 30 is chosen at random.
What is the probability, as a decimal, that it is a 2-digit number?
2.5
Calculating Probabilities
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Overview

0.375

Step-by-step explanation:

Listing the factors of 30

1, 2, 3, 5, 6, 10, 15, 30 ← that is 8 factors

There are 3,  2- digit factors, that is 10, 15, 30

Thus the probability of choosing a 2- digit number factor is

= 0.375

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2