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Finding the Fourth Proportional to 806.79, 1,112.52 and 638.47

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Solution

The fourth proportional to 806.79, 1,112.52 and 638.47 is: 880.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.79 : 1,112.52 = 638.47 : x
  2. Step 2: Convert to fraction form
    806.79/1,112.52 = 638.47/x
  3. Step 3: Cross multiply
    806.79x = 1,112.52 × 638.47
  4. Step 4: Simplify right side
    806.79x = 710,304.58
  5. Step 5: Solve for x
    x = 710,304.58/806.79
  6. Step 6: Final answer
    x = 880.40

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1.5x scale

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.