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Finding the Fourth Proportional to 538.50, 742.15 and 420.41

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Solution

The fourth proportional to 538.50, 742.15 and 420.41 is: 579.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.50 : 742.15 = 420.41 : x
  2. Step 2: Convert to fraction form
    538.50/742.15 = 420.41/x
  3. Step 3: Cross multiply
    538.50x = 742.15 × 420.41
  4. Step 4: Simplify right side
    538.50x = 312,005.18
  5. Step 5: Solve for x
    x = 312,005.18/538.50
  6. Step 6: Final answer
    x = 579.40

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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.