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Finding the Fourth Proportional to 521.15, 783.41 and 419.57

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Solution

The fourth proportional to 521.15, 783.41 and 419.57 is: 630.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.15 : 783.41 = 419.57 : x
  2. Step 2: Convert to fraction form
    521.15/783.41 = 419.57/x
  3. Step 3: Cross multiply
    521.15x = 783.41 × 419.57
  4. Step 4: Simplify right side
    521.15x = 328,689.32
  5. Step 5: Solve for x
    x = 328,689.32/521.15
  6. Step 6: Final answer
    x = 630.71

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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.