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Finding the Fourth Proportional to 1,286.39, 1,775.25 and 788.74

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Solution

The fourth proportional to 1,286.39, 1,775.25 and 788.74 is: 1,088.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.39 : 1,775.25 = 788.74 : x
  2. Step 2: Convert to fraction form
    1,286.39/1,775.25 = 788.74/x
  3. Step 3: Cross multiply
    1,286.39x = 1,775.25 × 788.74
  4. Step 4: Simplify right side
    1,286.39x = 1,400,215.12
  5. Step 5: Solve for x
    x = 1,400,215.12/1,286.39
  6. Step 6: Final answer
    x = 1,088.48

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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.