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Finding the Third Proportional to 858 and 978

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Solution

The third proportional to 858 and 978 is: 1,114.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    858 : 978 = 978 : x
  2. Step 2: Convert to fraction form
    858/978 = 978/x
  3. Step 3: Cross multiply
    858x = 978 × 978
  4. Step 4: Simplify right side
    858x = 956,484
  5. Step 5: Solve for x
    x = 956,484/858
  6. Step 6: Final answer
    x = 1,114.78

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