Home / 1,321.11-1,981.63-455.40

Finding the Fourth Proportional to 1,321.11, 1,981.63 and 455.40

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Solution

The fourth proportional to 1,321.11, 1,981.63 and 455.40 is: 683.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.11 : 1,981.63 = 455.40 : x
  2. Step 2: Convert to fraction form
    1,321.11/1,981.63 = 455.40/x
  3. Step 3: Cross multiply
    1,321.11x = 1,981.63 × 455.40
  4. Step 4: Simplify right side
    1,321.11x = 902,434.30
  5. Step 5: Solve for x
    x = 902,434.30/1,321.11
  6. Step 6: Final answer
    x = 683.09

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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.