Home / 1,289.60-1,935.38-509.81

Finding the Fourth Proportional to 1,289.60, 1,935.38 and 509.81

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Solution

The fourth proportional to 1,289.60, 1,935.38 and 509.81 is: 765.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.60 : 1,935.38 = 509.81 : x
  2. Step 2: Convert to fraction form
    1,289.60/1,935.38 = 509.81/x
  3. Step 3: Cross multiply
    1,289.60x = 1,935.38 × 509.81
  4. Step 4: Simplify right side
    1,289.60x = 986,675.69
  5. Step 5: Solve for x
    x = 986,675.69/1,289.60
  6. Step 6: Final answer
    x = 765.10

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.