Home / 1,298.53-1,945.90-640.20

Finding the Fourth Proportional to 1,298.53, 1,945.90 and 640.20

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Solution

The fourth proportional to 1,298.53, 1,945.90 and 640.20 is: 959.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,298.53 : 1,945.90 = 640.20 : x
  2. Step 2: Convert to fraction form
    1,298.53/1,945.90 = 640.20/x
  3. Step 3: Cross multiply
    1,298.53x = 1,945.90 × 640.20
  4. Step 4: Simplify right side
    1,298.53x = 1,245,765.18
  5. Step 5: Solve for x
    x = 1,245,765.18/1,298.53
  6. Step 6: Final answer
    x = 959.37

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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.