Set of four math problems requiring multiplication of whole numbers and fractions or mixed numbers.

Let’s solve each problem one by one, step by step.

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Problem 16: 9 × 8⁴⁄

First, turn the mixed number into an improper fraction:

8⁴⁄₅ = (8 × 5 + 4)/5 = (40 + 4)/5 = 44/5

Now multiply:
9 × 44/5 = (9 × 44) / 5 = 396 / 5

Convert back to a mixed number:
396 ÷ 5 = 79 with remainder 1 → 79¹⁄₅

✔ Check: 5 × 79 = 395, plus 1 = 396 → correct.

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Problem 17: 12 × 3³⁄₄

Turn 3³⁄₄ into improper fraction:
(3 × 4 + 3)/4 = (12 + 3)/4 = 15/4

Multiply:
12 × 15/4 = (12 × 15) / 4 = 180 / 4 = 45

✔ Check: 180 ÷ 4 = 45 → correct.

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Problem 18: ³⁄₄ × 9

Write 9 as 9/1:
³⁄₄ × 9/1 = (3 × 9) / (4 × 1) = 27/4

Convert to mixed number:
27 ÷ 4 = 6 with remainder 3 → 6³⁄₄

✔ Check: 4 × 6 = 24, plus 3 = 27 → correct.

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Problem 19: 3 × 5¹⁄₆

Turn 5¹⁄₆ into improper fraction:
(5 × 6 + 1)/6 = (30 + 1)/6 = 31/6

Multiply:
3 × 31/6 = (3 × 31) / 6 = 93 / 6

Simplify: divide numerator and denominator by 3 → 31/2

Convert to mixed number:
31 ÷ 2 = 15 with remainder 1 → 15¹⁄₂

✔ Check: 2 × 15 = 30, plus 1 = 31 → correct.

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Final Answer:
16) 79¹⁄₅
17) 45
18) 6³⁄₄
19) 15¹⁄₂