Home / 1,318.89-1,977.69-394.20

Finding the Fourth Proportional to 1,318.89, 1,977.69 and 394.20

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Solution

The fourth proportional to 1,318.89, 1,977.69 and 394.20 is: 591.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,318.89 : 1,977.69 = 394.20 : x
  2. Step 2: Convert to fraction form
    1,318.89/1,977.69 = 394.20/x
  3. Step 3: Cross multiply
    1,318.89x = 1,977.69 × 394.20
  4. Step 4: Simplify right side
    1,318.89x = 779,605.40
  5. Step 5: Solve for x
    x = 779,605.40/1,318.89
  6. Step 6: Final answer
    x = 591.11

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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.