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Finding the Fourth Proportional to 803.60, 1,107.88 and 638.36

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Solution

The fourth proportional to 803.60, 1,107.88 and 638.36 is: 880.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    803.60 : 1,107.88 = 638.36 : x
  2. Step 2: Convert to fraction form
    803.60/1,107.88 = 638.36/x
  3. Step 3: Cross multiply
    803.60x = 1,107.88 × 638.36
  4. Step 4: Simplify right side
    803.60x = 707,226.28
  5. Step 5: Solve for x
    x = 707,226.28/803.60
  6. Step 6: Final answer
    x = 880.07

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.