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Finding the Fourth Proportional to 691.40, 954.24 and 392.70

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Solution

The fourth proportional to 691.40, 954.24 and 392.70 is: 541.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.40 : 954.24 = 392.70 : x
  2. Step 2: Convert to fraction form
    691.40/954.24 = 392.70/x
  3. Step 3: Cross multiply
    691.40x = 954.24 × 392.70
  4. Step 4: Simplify right side
    691.40x = 374,730.05
  5. Step 5: Solve for x
    x = 374,730.05/691.40
  6. Step 6: Final answer
    x = 541.99

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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.