Home / 1,320.81-1,981.31-346.89

Finding the Fourth Proportional to 1,320.81, 1,981.31 and 346.89

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Solution

The fourth proportional to 1,320.81, 1,981.31 and 346.89 is: 520.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,320.81 : 1,981.31 = 346.89 : x
  2. Step 2: Convert to fraction form
    1,320.81/1,981.31 = 346.89/x
  3. Step 3: Cross multiply
    1,320.81x = 1,981.31 × 346.89
  4. Step 4: Simplify right side
    1,320.81x = 687,296.63
  5. Step 5: Solve for x
    x = 687,296.63/1,320.81
  6. Step 6: Final answer
    x = 520.36

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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.