You are asked to write all numbers from 50 to 99 without the digits 2 and 7 How many numbers you wou...........

Math and Mental Ability Permutation & Combination

You are asked to write all numbers from 50 to 99 without the digits 2 and 7. How many numbers you would write?

- You're tasked with writing numbers from 50 to 99, omitting those containing digits "2" and "7."

- Identify eligible numbers:

- Tens place ranges from 5 to 9 since numbers start from 50.

- For 50-59, exclude 52 and 57. Remaining: 50, 51, 53, 54, 55, 56, 58, 59.

- For 60-69, exclude 62 and 67. Remaining: 60, 61, 63, 64, 65, 66, 68, 69.

- For 70-79, all are excluded because they contain "7."

- For 80-89, exclude 82 and 87. Remaining: 80, 81, 83, 84, 85, 86, 88, 89.

- For 90-99, exclude 92 and 97. Remaining: 90, 91, 93, 94, 95, 96, 98, 99.

- Count all remaining numbers: 8 from 50-59, 8 from 60-69, 0 from 70-79, 8 from 80-89, and 8 from 90-99. Total: 32 numbers.

Option:1, 32 is the correct answer.

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