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Finding the Third Proportional to 1,140 and 1,239

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Solution

The third proportional to 1,140 and 1,239 is: 1,346.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,140 : 1,239 = 1,239 : x
  2. Step 2: Convert to fraction form
    1,140/1,239 = 1,239/x
  3. Step 3: Cross multiply
    1,140x = 1,239 × 1,239
  4. Step 4: Simplify right side
    1,140x = 1,535,121
  5. Step 5: Solve for x
    x = 1,535,121/1,140
  6. Step 6: Final answer
    x = 1,346.60

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Why These Related Problems?

These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.