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Finding the Fourth Proportional to 804.42, 1,111.46 and 639.86

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Solution

The fourth proportional to 804.42, 1,111.46 and 639.86 is: 884.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    804.42 : 1,111.46 = 639.86 : x
  2. Step 2: Convert to fraction form
    804.42/1,111.46 = 639.86/x
  3. Step 3: Cross multiply
    804.42x = 1,111.46 × 639.86
  4. Step 4: Simplify right side
    804.42x = 711,170.04
  5. Step 5: Solve for x
    x = 711,170.04/804.42
  6. Step 6: Final answer
    x = 884.08

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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.