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Finding the Fourth Proportional to 780.57, 1,077.57 and 486.27

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Solution

The fourth proportional to 780.57, 1,077.57 and 486.27 is: 671.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.57 : 1,077.57 = 486.27 : x
  2. Step 2: Convert to fraction form
    780.57/1,077.57 = 486.27/x
  3. Step 3: Cross multiply
    780.57x = 1,077.57 × 486.27
  4. Step 4: Simplify right side
    780.57x = 523,989.96
  5. Step 5: Solve for x
    x = 523,989.96/780.57
  6. Step 6: Final answer
    x = 671.29

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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.