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Finding the Fourth Proportional to 430.79, 648.71 and 309.90

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Solution

The fourth proportional to 430.79, 648.71 and 309.90 is: 466.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.79 : 648.71 = 309.90 : x
  2. Step 2: Convert to fraction form
    430.79/648.71 = 309.90/x
  3. Step 3: Cross multiply
    430.79x = 648.71 × 309.90
  4. Step 4: Simplify right side
    430.79x = 201,035.23
  5. Step 5: Solve for x
    x = 201,035.23/430.79
  6. Step 6: Final answer
    x = 466.67

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.