Home / 1,289.61-1,778.58-917.82

Finding the Fourth Proportional to 1,289.61, 1,778.58 and 917.82

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Solution

The fourth proportional to 1,289.61, 1,778.58 and 917.82 is: 1,265.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.61 : 1,778.58 = 917.82 : x
  2. Step 2: Convert to fraction form
    1,289.61/1,778.58 = 917.82/x
  3. Step 3: Cross multiply
    1,289.61x = 1,778.58 × 917.82
  4. Step 4: Simplify right side
    1,289.61x = 1,632,416.30
  5. Step 5: Solve for x
    x = 1,632,416.30/1,289.61
  6. Step 6: Final answer
    x = 1,265.82

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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.