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Finding the Fourth Proportional to 423.90, 637.20 and 399.60

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Solution

The fourth proportional to 423.90, 637.20 and 399.60 is: 600.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.90 : 637.20 = 399.60 : x
  2. Step 2: Convert to fraction form
    423.90/637.20 = 399.60/x
  3. Step 3: Cross multiply
    423.90x = 637.20 × 399.60
  4. Step 4: Simplify right side
    423.90x = 254,625.12
  5. Step 5: Solve for x
    x = 254,625.12/423.90
  6. Step 6: Final answer
    x = 600.67

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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.