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Finding the Fourth Proportional to 948.28, 1,423.08 and 640.72

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Solution

The fourth proportional to 948.28, 1,423.08 and 640.72 is: 961.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    948.28 : 1,423.08 = 640.72 : x
  2. Step 2: Convert to fraction form
    948.28/1,423.08 = 640.72/x
  3. Step 3: Cross multiply
    948.28x = 1,423.08 × 640.72
  4. Step 4: Simplify right side
    948.28x = 911,795.82
  5. Step 5: Solve for x
    x = 911,795.82/948.28
  6. Step 6: Final answer
    x = 961.53

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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.