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Finding the Fourth Proportional to 428.22, 637.88 and 418.50

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Solution

The fourth proportional to 428.22, 637.88 and 418.50 is: 623.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.22 : 637.88 = 418.50 : x
  2. Step 2: Convert to fraction form
    428.22/637.88 = 418.50/x
  3. Step 3: Cross multiply
    428.22x = 637.88 × 418.50
  4. Step 4: Simplify right side
    428.22x = 266,950.69
  5. Step 5: Solve for x
    x = 266,950.69/428.22
  6. Step 6: Final answer
    x = 623.40

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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.