How do you solve 23?

Problem 22

You have the correct answer since there are 9 non-white socks out of 15 total.

Problem 23

Explanation:

We have 10 blue marbles and 10+4+5+6 = 14+11 = 25 marbles total

This means there are 25-10 = 15 non-blue marbles.

The probability of selecting a non-blue marble is 15/25. I won't reduce this as we'll use this fraction to set up the next probability.

Because the marble is not replaced, this means we go from 15 non-blue marbles to 15-1 = 14 non-blue marbles. We also go from 25 total marbles to 25-1 = 24 total.

In short, the fraction 15/25 turns into 14/24 after subtracting 1 from each part.

Let's reduce each fraction mentioned

15/25 = (3*5)/(5*5) = 3/5

14/24 = (2*7)/(2*12) = 7/12

Then we'll multiply the two reduced fractions

(3/5)*(7/12) = (3*7)/(5*12) = 21/60

Lastly, we'll reduce that result

21/60 = (3*7)/(3*20) = 7/20

The probability of selecting two marbles that aren't blue is 7/20. This is done without replacement.

As a shortcut, we could say:

(15/25)*(14/24) = 7/20

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

22 dimes and 9 nickels

step-by-step explanation: