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Finding the Fourth Proportional to 838.34, 1,256.81 and 399.35

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Solution

The fourth proportional to 838.34, 1,256.81 and 399.35 is: 598.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.34 : 1,256.81 = 399.35 : x
  2. Step 2: Convert to fraction form
    838.34/1,256.81 = 399.35/x
  3. Step 3: Cross multiply
    838.34x = 1,256.81 × 399.35
  4. Step 4: Simplify right side
    838.34x = 501,898.79
  5. Step 5: Solve for x
    x = 501,898.79/838.34
  6. Step 6: Final answer
    x = 598.69

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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.