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Finding the Fourth Proportional to 328.59, 489.51 and 312.80

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Solution

The fourth proportional to 328.59, 489.51 and 312.80 is: 465.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.59 : 489.51 = 312.80 : x
  2. Step 2: Convert to fraction form
    328.59/489.51 = 312.80/x
  3. Step 3: Cross multiply
    328.59x = 489.51 × 312.80
  4. Step 4: Simplify right side
    328.59x = 153,116.28
  5. Step 5: Solve for x
    x = 153,116.28/328.59
  6. Step 6: Final answer
    x = 465.98

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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.