9514 1404 393
Answer:
5a,b = 17,576,000; 11,232,000
6. 45,697,600; 32,292,000
7. 6,760,000; 3,276,000
8. 118,813,760; 78,936,000
Explanation:
The number of possible ways the characters can occur is the product of the numbers of ways a character can be selected in each position. If letters or digits cannot repeat, the number of possible selections is reduced by 1 in each new location.
5a. 26×26×26×10×10×10 = 26³×10³ = 17,576,000
5b. 26×25×24×10×9×8 = 11,232,000
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6a. 10²×26⁴ = 45,697,600
6b. 10×9×26×25×24×23 = 32,292,000
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7a. 10⁴×26² = 6,760,000
7b. 10×9×8×7×26×25 = 3,276,000
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8a. 26⁵×10 = 118,813,760
8b. 26×25×24×23×22×10 = 78,936,000