Home / 1,314.20-1,971.30-389.72

Finding the Fourth Proportional to 1,314.20, 1,971.30 and 389.72

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Solution

The fourth proportional to 1,314.20, 1,971.30 and 389.72 is: 584.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,314.20 : 1,971.30 = 389.72 : x
  2. Step 2: Convert to fraction form
    1,314.20/1,971.30 = 389.72/x
  3. Step 3: Cross multiply
    1,314.20x = 1,971.30 × 389.72
  4. Step 4: Simplify right side
    1,314.20x = 768,255.04
  5. Step 5: Solve for x
    x = 768,255.04/1,314.20
  6. Step 6: Final answer
    x = 584.58

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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.