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Finding the Fourth Proportional to 639.12, 957.60 and 446.88

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Solution

The fourth proportional to 639.12, 957.60 and 446.88 is: 669.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.12 : 957.60 = 446.88 : x
  2. Step 2: Convert to fraction form
    639.12/957.60 = 446.88/x
  3. Step 3: Cross multiply
    639.12x = 957.60 × 446.88
  4. Step 4: Simplify right side
    639.12x = 427,932.29
  5. Step 5: Solve for x
    x = 427,932.29/639.12
  6. Step 6: Final answer
    x = 669.56

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.