Home / 1,290.60-1,935.19-509.81

Finding the Fourth Proportional to 1,290.60, 1,935.19 and 509.81

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Solution

The fourth proportional to 1,290.60, 1,935.19 and 509.81 is: 764.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.60 : 1,935.19 = 509.81 : x
  2. Step 2: Convert to fraction form
    1,290.60/1,935.19 = 509.81/x
  3. Step 3: Cross multiply
    1,290.60x = 1,935.19 × 509.81
  4. Step 4: Simplify right side
    1,290.60x = 986,581.06
  5. Step 5: Solve for x
    x = 986,581.06/1,290.60
  6. Step 6: Final answer
    x = 764.44

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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.