Question 265049
The multiples of 3 that are included in
houses numbered 100-150 are:
34 x 3 = 102
35 x 3 = 105
36 x 3 = 108
up to:
50 x 3 = 150
And the multiples of 5 are:
20 x 5 = 100
21 x 5 = 105
22 x 5 = 110
up to
30 x 5 = 150
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I don't want to count house numbers twice, so
in the 1st list I'll pull out thoses divisible by 5
35 x 3
40 x 3
45 x 3
50 x 3
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The 1st list has {{{50 - 34 + 1 = 17}}} entries
I want to delete 4
{{{17 - 4 = 13}}}
The 2nd list has {{{30 - 20 + 1 = 11}}} entries
{{{13 + 11 = 24}}}
There are 24 house numbers she doesn't want
{{{150 - 100 + 1 = 51}}} possible numbers
{{{51 - 24 = 27}}}
She can choose from 27 houses
Hope I got it right!