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Finding the Fourth Proportional to 427.51, 641.78 and 288.80

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Solution

The fourth proportional to 427.51, 641.78 and 288.80 is: 433.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.51 : 641.78 = 288.80 : x
  2. Step 2: Convert to fraction form
    427.51/641.78 = 288.80/x
  3. Step 3: Cross multiply
    427.51x = 641.78 × 288.80
  4. Step 4: Simplify right side
    427.51x = 185,346.06
  5. Step 5: Solve for x
    x = 185,346.06/427.51
  6. Step 6: Final answer
    x = 433.55

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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.