Home / 1,209.13-1,666.26-815.47

Finding the Fourth Proportional to 1,209.13, 1,666.26 and 815.47

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Solution

The fourth proportional to 1,209.13, 1,666.26 and 815.47 is: 1,123.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209.13 : 1,666.26 = 815.47 : x
  2. Step 2: Convert to fraction form
    1,209.13/1,666.26 = 815.47/x
  3. Step 3: Cross multiply
    1,209.13x = 1,666.26 × 815.47
  4. Step 4: Simplify right side
    1,209.13x = 1,358,785.04
  5. Step 5: Solve for x
    x = 1,358,785.04/1,209.13
  6. Step 6: Final answer
    x = 1,123.77

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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.