Home / 1,127.20-1,555.40-629.80

Finding the Fourth Proportional to 1,127.20, 1,555.40 and 629.80

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Solution

The fourth proportional to 1,127.20, 1,555.40 and 629.80 is: 869.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,127.20 : 1,555.40 = 629.80 : x
  2. Step 2: Convert to fraction form
    1,127.20/1,555.40 = 629.80/x
  3. Step 3: Cross multiply
    1,127.20x = 1,555.40 × 629.80
  4. Step 4: Simplify right side
    1,127.20x = 979,590.92
  5. Step 5: Solve for x
    x = 979,590.92/1,127.20
  6. Step 6: Final answer
    x = 869.05

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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.