Home / 1,128.14-1,688.11-931.31

Finding the Fourth Proportional to 1,128.14, 1,688.11 and 931.31

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Solution

The fourth proportional to 1,128.14, 1,688.11 and 931.31 is: 1,393.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,128.14 : 1,688.11 = 931.31 : x
  2. Step 2: Convert to fraction form
    1,128.14/1,688.11 = 931.31/x
  3. Step 3: Cross multiply
    1,128.14x = 1,688.11 × 931.31
  4. Step 4: Simplify right side
    1,128.14x = 1,572,144.85
  5. Step 5: Solve for x
    x = 1,572,144.85/1,128.14
  6. Step 6: Final answer
    x = 1,393.58

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.