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Finding the Fourth Proportional to 959, 1,438.50 and 309.78

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Solution

The fourth proportional to 959, 1,438.50 and 309.78 is: 464.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    959 : 1,438.50 = 309.78 : x
  2. Step 2: Convert to fraction form
    959/1,438.50 = 309.78/x
  3. Step 3: Cross multiply
    959x = 1,438.50 × 309.78
  4. Step 4: Simplify right side
    959x = 445,618.53
  5. Step 5: Solve for x
    x = 445,618.53/959
  6. Step 6: Final answer
    x = 464.67

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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.