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Finding the Fourth Proportional to 328.26, 489.75 and 312.78

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Solution

The fourth proportional to 328.26, 489.75 and 312.78 is: 466.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.26 : 489.75 = 312.78 : x
  2. Step 2: Convert to fraction form
    328.26/489.75 = 312.78/x
  3. Step 3: Cross multiply
    328.26x = 489.75 × 312.78
  4. Step 4: Simplify right side
    328.26x = 153,184.01
  5. Step 5: Solve for x
    x = 153,184.01/328.26
  6. Step 6: Final answer
    x = 466.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.