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Finding the Fourth Proportional to 485.98, 670.65 and 289.51

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Solution

The fourth proportional to 485.98, 670.65 and 289.51 is: 399.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.98 : 670.65 = 289.51 : x
  2. Step 2: Convert to fraction form
    485.98/670.65 = 289.51/x
  3. Step 3: Cross multiply
    485.98x = 670.65 × 289.51
  4. Step 4: Simplify right side
    485.98x = 194,159.88
  5. Step 5: Solve for x
    x = 194,159.88/485.98
  6. Step 6: Final answer
    x = 399.52

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.