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Finding the Fourth Proportional to 665.64, 998.78 and 319.37

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Solution

The fourth proportional to 665.64, 998.78 and 319.37 is: 479.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.64 : 998.78 = 319.37 : x
  2. Step 2: Convert to fraction form
    665.64/998.78 = 319.37/x
  3. Step 3: Cross multiply
    665.64x = 998.78 × 319.37
  4. Step 4: Simplify right side
    665.64x = 318,973.78
  5. Step 5: Solve for x
    x = 318,973.78/665.64
  6. Step 6: Final answer
    x = 479.20

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1.5x scale

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.