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Finding the Fourth Proportional to 421.42, 578.45 and 373.78

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Solution

The fourth proportional to 421.42, 578.45 and 373.78 is: 513.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.42 : 578.45 = 373.78 : x
  2. Step 2: Convert to fraction form
    421.42/578.45 = 373.78/x
  3. Step 3: Cross multiply
    421.42x = 578.45 × 373.78
  4. Step 4: Simplify right side
    421.42x = 216,213.04
  5. Step 5: Solve for x
    x = 216,213.04/421.42
  6. Step 6: Final answer
    x = 513.06

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.