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Finding the Fourth Proportional to 1,289.91, 1,780.07 and 730.37

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Solution

The fourth proportional to 1,289.91, 1,780.07 and 730.37 is: 1,007.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.91 : 1,780.07 = 730.37 : x
  2. Step 2: Convert to fraction form
    1,289.91/1,780.07 = 730.37/x
  3. Step 3: Cross multiply
    1,289.91x = 1,780.07 × 730.37
  4. Step 4: Simplify right side
    1,289.91x = 1,300,110.52
  5. Step 5: Solve for x
    x = 1,300,110.52/1,289.91
  6. Step 6: Final answer
    x = 1,007.91

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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.