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Finding the Fourth Proportional to 428.50, 646.12 and 348.31

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Solution

The fourth proportional to 428.50, 646.12 and 348.31 is: 525.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.50 : 646.12 = 348.31 : x
  2. Step 2: Convert to fraction form
    428.50/646.12 = 348.31/x
  3. Step 3: Cross multiply
    428.50x = 646.12 × 348.31
  4. Step 4: Simplify right side
    428.50x = 225,050.06
  5. Step 5: Solve for x
    x = 225,050.06/428.50
  6. Step 6: Final answer
    x = 525.20

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.