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Finding the Fourth Proportional to 661.38, 912.90 and 487.23

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Solution

The fourth proportional to 661.38, 912.90 and 487.23 is: 672.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.38 : 912.90 = 487.23 : x
  2. Step 2: Convert to fraction form
    661.38/912.90 = 487.23/x
  3. Step 3: Cross multiply
    661.38x = 912.90 × 487.23
  4. Step 4: Simplify right side
    661.38x = 444,792.27
  5. Step 5: Solve for x
    x = 444,792.27/661.38
  6. Step 6: Final answer
    x = 672.52

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Double scale
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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.