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Finding the Fourth Proportional to 840.07, 1,159.41 and 643.24

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Solution

The fourth proportional to 840.07, 1,159.41 and 643.24 is: 887.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.07 : 1,159.41 = 643.24 : x
  2. Step 2: Convert to fraction form
    840.07/1,159.41 = 643.24/x
  3. Step 3: Cross multiply
    840.07x = 1,159.41 × 643.24
  4. Step 4: Simplify right side
    840.07x = 745,778.89
  5. Step 5: Solve for x
    x = 745,778.89/840.07
  6. Step 6: Final answer
    x = 887.76

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.