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Finding the Fourth Proportional to 613.40, 915.37 and 505.40

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Solution

The fourth proportional to 613.40, 915.37 and 505.40 is: 754.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.40 : 915.37 = 505.40 : x
  2. Step 2: Convert to fraction form
    613.40/915.37 = 505.40/x
  3. Step 3: Cross multiply
    613.40x = 915.37 × 505.40
  4. Step 4: Simplify right side
    613.40x = 462,628.00
  5. Step 5: Solve for x
    x = 462,628.00/613.40
  6. Step 6: Final answer
    x = 754.20

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.