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Finding the Fourth Proportional to 642.66, 885.70 and 613.50

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Solution

The fourth proportional to 642.66, 885.70 and 613.50 is: 845.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.66 : 885.70 = 613.50 : x
  2. Step 2: Convert to fraction form
    642.66/885.70 = 613.50/x
  3. Step 3: Cross multiply
    642.66x = 885.70 × 613.50
  4. Step 4: Simplify right side
    642.66x = 543,376.95
  5. Step 5: Solve for x
    x = 543,376.95/642.66
  6. Step 6: Final answer
    x = 845.51

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.