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Finding the Fourth Proportional to 660.19, 989.69 and 313.31

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Solution

The fourth proportional to 660.19, 989.69 and 313.31 is: 469.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.19 : 989.69 = 313.31 : x
  2. Step 2: Convert to fraction form
    660.19/989.69 = 313.31/x
  3. Step 3: Cross multiply
    660.19x = 989.69 × 313.31
  4. Step 4: Simplify right side
    660.19x = 310,074.83
  5. Step 5: Solve for x
    x = 310,074.83/660.19
  6. Step 6: Final answer
    x = 469.68

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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.