Home / 1,289.31-1,932.93-640.50

Finding the Fourth Proportional to 1,289.31, 1,932.93 and 640.50

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Solution

The fourth proportional to 1,289.31, 1,932.93 and 640.50 is: 960.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.31 : 1,932.93 = 640.50 : x
  2. Step 2: Convert to fraction form
    1,289.31/1,932.93 = 640.50/x
  3. Step 3: Cross multiply
    1,289.31x = 1,932.93 × 640.50
  4. Step 4: Simplify right side
    1,289.31x = 1,238,041.67
  5. Step 5: Solve for x
    x = 1,238,041.67/1,289.31
  6. Step 6: Final answer
    x = 960.24

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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.