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Finding the Fourth Proportional to 930.81, 1,284.72 and 636.78

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Solution

The fourth proportional to 930.81, 1,284.72 and 636.78 is: 878.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    930.81 : 1,284.72 = 636.78 : x
  2. Step 2: Convert to fraction form
    930.81/1,284.72 = 636.78/x
  3. Step 3: Cross multiply
    930.81x = 1,284.72 × 636.78
  4. Step 4: Simplify right side
    930.81x = 818,084.00
  5. Step 5: Solve for x
    x = 818,084.00/930.81
  6. Step 6: Final answer
    x = 878.89

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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.