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Finding the Fourth Proportional to 666.91, 920.39 and 372.20

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Solution

The fourth proportional to 666.91, 920.39 and 372.20 is: 513.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.91 : 920.39 = 372.20 : x
  2. Step 2: Convert to fraction form
    666.91/920.39 = 372.20/x
  3. Step 3: Cross multiply
    666.91x = 920.39 × 372.20
  4. Step 4: Simplify right side
    666.91x = 342,569.16
  5. Step 5: Solve for x
    x = 342,569.16/666.91
  6. Step 6: Final answer
    x = 513.67

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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.