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Finding the Fourth Proportional to 421.58, 633.72 and 399.98

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Solution

The fourth proportional to 421.58, 633.72 and 399.98 is: 601.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.58 : 633.72 = 399.98 : x
  2. Step 2: Convert to fraction form
    421.58/633.72 = 399.98/x
  3. Step 3: Cross multiply
    421.58x = 633.72 × 399.98
  4. Step 4: Simplify right side
    421.58x = 253,475.33
  5. Step 5: Solve for x
    x = 253,475.33/421.58
  6. Step 6: Final answer
    x = 601.25

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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.