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Finding the Fourth Proportional to 520.47, 780.50 and 260.40

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Solution

The fourth proportional to 520.47, 780.50 and 260.40 is: 390.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.47 : 780.50 = 260.40 : x
  2. Step 2: Convert to fraction form
    520.47/780.50 = 260.40/x
  3. Step 3: Cross multiply
    520.47x = 780.50 × 260.40
  4. Step 4: Simplify right side
    520.47x = 203,240.90
  5. Step 5: Solve for x
    x = 203,240.90/520.47
  6. Step 6: Final answer
    x = 390.49

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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.