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Finding the Fourth Proportional to 521.94, 782.10 and 278.40

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Solution

The fourth proportional to 521.94, 782.10 and 278.40 is: 417.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.94 : 782.10 = 278.40 : x
  2. Step 2: Convert to fraction form
    521.94/782.10 = 278.40/x
  3. Step 3: Cross multiply
    521.94x = 782.10 × 278.40
  4. Step 4: Simplify right side
    521.94x = 217,736.64
  5. Step 5: Solve for x
    x = 217,736.64/521.94
  6. Step 6: Final answer
    x = 417.17

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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.