Home / 1,039.20-1,434.40-646.80

Finding the Fourth Proportional to 1,039.20, 1,434.40 and 646.80

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Solution

The fourth proportional to 1,039.20, 1,434.40 and 646.80 is: 892.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,039.20 : 1,434.40 = 646.80 : x
  2. Step 2: Convert to fraction form
    1,039.20/1,434.40 = 646.80/x
  3. Step 3: Cross multiply
    1,039.20x = 1,434.40 × 646.80
  4. Step 4: Simplify right side
    1,039.20x = 927,769.92
  5. Step 5: Solve for x
    x = 927,769.92/1,039.20
  6. Step 6: Final answer
    x = 892.77

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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.