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Finding the Fourth Proportional to 783.64, 1,081.48 and 489.02

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Solution

The fourth proportional to 783.64, 1,081.48 and 489.02 is: 674.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    783.64 : 1,081.48 = 489.02 : x
  2. Step 2: Convert to fraction form
    783.64/1,081.48 = 489.02/x
  3. Step 3: Cross multiply
    783.64x = 1,081.48 × 489.02
  4. Step 4: Simplify right side
    783.64x = 528,865.35
  5. Step 5: Solve for x
    x = 528,865.35/783.64
  6. Step 6: Final answer
    x = 674.88

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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.