Home / 820.13-1,131.80-470.79

Finding the Fourth Proportional to 820.13, 1,131.80 and 470.79

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Solution

The fourth proportional to 820.13, 1,131.80 and 470.79 is: 649.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.13 : 1,131.80 = 470.79 : x
  2. Step 2: Convert to fraction form
    820.13/1,131.80 = 470.79/x
  3. Step 3: Cross multiply
    820.13x = 1,131.80 × 470.79
  4. Step 4: Simplify right side
    820.13x = 532,837.77
  5. Step 5: Solve for x
    x = 532,837.77/820.13
  6. Step 6: Final answer
    x = 649.70

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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.