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Finding the Fourth Proportional to 786.78, 1,085.38 and 471.89

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Solution

The fourth proportional to 786.78, 1,085.38 and 471.89 is: 650.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    786.78 : 1,085.38 = 471.89 : x
  2. Step 2: Convert to fraction form
    786.78/1,085.38 = 471.89/x
  3. Step 3: Cross multiply
    786.78x = 1,085.38 × 471.89
  4. Step 4: Simplify right side
    786.78x = 512,179.97
  5. Step 5: Solve for x
    x = 512,179.97/786.78
  6. Step 6: Final answer
    x = 650.98

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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.