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Finding the Fourth Proportional to 319.80, 438.50 and 288.59

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Solution

The fourth proportional to 319.80, 438.50 and 288.59 is: 395.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.80 : 438.50 = 288.59 : x
  2. Step 2: Convert to fraction form
    319.80/438.50 = 288.59/x
  3. Step 3: Cross multiply
    319.80x = 438.50 × 288.59
  4. Step 4: Simplify right side
    319.80x = 126,546.37
  5. Step 5: Solve for x
    x = 126,546.37/319.80
  6. Step 6: Final answer
    x = 395.70

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.