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Finding the Fourth Proportional to 561.03, 840.75 and 287.31

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Solution

The fourth proportional to 561.03, 840.75 and 287.31 is: 430.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.03 : 840.75 = 287.31 : x
  2. Step 2: Convert to fraction form
    561.03/840.75 = 287.31/x
  3. Step 3: Cross multiply
    561.03x = 840.75 × 287.31
  4. Step 4: Simplify right side
    561.03x = 241,555.88
  5. Step 5: Solve for x
    x = 241,555.88/561.03
  6. Step 6: Final answer
    x = 430.56

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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.