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Please help! Will mark Brainliest if the answer given is correct!

We call a number peachy if every digit in the number is either a $3$ or next to a 3 For example, the numbers 333,83, 303, and 3773 are all peachy, but the numbers 32523, 786, 340, and 3999 are not peachy.


How many positive 2digit numbers are peachy?

Respuesta :

Answer:

19

Step-by-step explanation:

All numbers which start with a 3 are peachy: {30, 31, 32, 33, 34, 35, 36, 37, 38 and 39}

All numbers which finish with a 3 are peachy: {03, 13, 23, 43, 53, 63, 73, 83 and 93} (33 was included in the previous list)

There are 10 numbers in the first list and 9 in the second list. Therefore, there are 19 peachy positive 2 digit numbers

suviadi164

Answer:

18

Step-by-step explanation:

The answer to this question is 18 by simple casework.

First, let's note that there are 90 numbers that could be possible solutions to this problem and that we need to create a where one or two of the digits in a number are 3.

so _3

or 3_

or 33

in the first, there are 8 options for the number (it cannot be a 3 and it cannot be a zero)

in the second, there are 9 options for the number (it cannot be a 3 but it can be a zero)

8 + 9 + 1= 18 possible numbers (out of 90 2 digit numbers)

(note: jblain had the wrong answer only due to a slight error where they accidentally included 03 in their options, which is not correct because the number needs to be 2 digits)

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