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Finding the Fourth Proportional to 689.78, 951.89 and 513.53

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Solution

The fourth proportional to 689.78, 951.89 and 513.53 is: 708.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.78 : 951.89 = 513.53 : x
  2. Step 2: Convert to fraction form
    689.78/951.89 = 513.53/x
  3. Step 3: Cross multiply
    689.78x = 951.89 × 513.53
  4. Step 4: Simplify right side
    689.78x = 488,818.77
  5. Step 5: Solve for x
    x = 488,818.77/689.78
  6. Step 6: Final answer
    x = 708.66

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1.5x scale

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.