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Finding the Fourth Proportional to 660.74, 990.37 and 313.79

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Solution

The fourth proportional to 660.74, 990.37 and 313.79 is: 470.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.74 : 990.37 = 313.79 : x
  2. Step 2: Convert to fraction form
    660.74/990.37 = 313.79/x
  3. Step 3: Cross multiply
    660.74x = 990.37 × 313.79
  4. Step 4: Simplify right side
    660.74x = 310,771.07
  5. Step 5: Solve for x
    x = 310,771.07/660.74
  6. Step 6: Final answer
    x = 470.34

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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.