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Finding the Fourth Proportional to 779.96, 1,073.88 and 646.64

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Solution

The fourth proportional to 779.96, 1,073.88 and 646.64 is: 890.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.96 : 1,073.88 = 646.64 : x
  2. Step 2: Convert to fraction form
    779.96/1,073.88 = 646.64/x
  3. Step 3: Cross multiply
    779.96x = 1,073.88 × 646.64
  4. Step 4: Simplify right side
    779.96x = 694,413.76
  5. Step 5: Solve for x
    x = 694,413.76/779.96
  6. Step 6: Final answer
    x = 890.32

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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.