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Finding the Fourth Proportional to 783.72, 1,081.38 and 628.84

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Solution

The fourth proportional to 783.72, 1,081.38 and 628.84 is: 867.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    783.72 : 1,081.38 = 628.84 : x
  2. Step 2: Convert to fraction form
    783.72/1,081.38 = 628.84/x
  3. Step 3: Cross multiply
    783.72x = 1,081.38 × 628.84
  4. Step 4: Simplify right side
    783.72x = 680,015.00
  5. Step 5: Solve for x
    x = 680,015.00/783.72
  6. Step 6: Final answer
    x = 867.68

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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.