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Finding the Fourth Proportional to 399.40, 598.54 and 155.78

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Solution

The fourth proportional to 399.40, 598.54 and 155.78 is: 233.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.40 : 598.54 = 155.78 : x
  2. Step 2: Convert to fraction form
    399.40/598.54 = 155.78/x
  3. Step 3: Cross multiply
    399.40x = 598.54 × 155.78
  4. Step 4: Simplify right side
    399.40x = 93,240.56
  5. Step 5: Solve for x
    x = 93,240.56/399.40
  6. Step 6: Final answer
    x = 233.45

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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.