Home / 1,129.40-1,558.50-631.80

Finding the Fourth Proportional to 1,129.40, 1,558.50 and 631.80

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Solution

The fourth proportional to 1,129.40, 1,558.50 and 631.80 is: 871.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,129.40 : 1,558.50 = 631.80 : x
  2. Step 2: Convert to fraction form
    1,129.40/1,558.50 = 631.80/x
  3. Step 3: Cross multiply
    1,129.40x = 1,558.50 × 631.80
  4. Step 4: Simplify right side
    1,129.40x = 984,660.30
  5. Step 5: Solve for x
    x = 984,660.30/1,129.40
  6. Step 6: Final answer
    x = 871.84

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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.