Home / 1,137.13-1,569.30-639.80

Finding the Fourth Proportional to 1,137.13, 1,569.30 and 639.80

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Solution

The fourth proportional to 1,137.13, 1,569.30 and 639.80 is: 882.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,137.13 : 1,569.30 = 639.80 : x
  2. Step 2: Convert to fraction form
    1,137.13/1,569.30 = 639.80/x
  3. Step 3: Cross multiply
    1,137.13x = 1,569.30 × 639.80
  4. Step 4: Simplify right side
    1,137.13x = 1,004,042.06
  5. Step 5: Solve for x
    x = 1,004,042.06/1,137.13
  6. Step 6: Final answer
    x = 882.96

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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.