Home / 820.20-1,131.80-470.88

Finding the Fourth Proportional to 820.20, 1,131.80 and 470.88

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Solution

The fourth proportional to 820.20, 1,131.80 and 470.88 is: 649.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.20 : 1,131.80 = 470.88 : x
  2. Step 2: Convert to fraction form
    820.20/1,131.80 = 470.88/x
  3. Step 3: Cross multiply
    820.20x = 1,131.80 × 470.88
  4. Step 4: Simplify right side
    820.20x = 532,941.98
  5. Step 5: Solve for x
    x = 532,941.98/820.20
  6. Step 6: Final answer
    x = 649.77

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.