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Finding the Fourth Proportional to 430.29, 642.32 and 378.39

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Solution

The fourth proportional to 430.29, 642.32 and 378.39 is: 564.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.29 : 642.32 = 378.39 : x
  2. Step 2: Convert to fraction form
    430.29/642.32 = 378.39/x
  3. Step 3: Cross multiply
    430.29x = 642.32 × 378.39
  4. Step 4: Simplify right side
    430.29x = 243,045.57
  5. Step 5: Solve for x
    x = 243,045.57/430.29
  6. Step 6: Final answer
    x = 564.84

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.