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Finding the Fourth Proportional to 781.45, 1,078.41 and 501.69

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Solution

The fourth proportional to 781.45, 1,078.41 and 501.69 is: 692.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.45 : 1,078.41 = 501.69 : x
  2. Step 2: Convert to fraction form
    781.45/1,078.41 = 501.69/x
  3. Step 3: Cross multiply
    781.45x = 1,078.41 × 501.69
  4. Step 4: Simplify right side
    781.45x = 541,025.00
  5. Step 5: Solve for x
    x = 541,025.00/781.45
  6. Step 6: Final answer
    x = 692.34

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Double scale
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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.