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Finding the Fourth Proportional to 485.29, 669.63 and 278.25

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Solution

The fourth proportional to 485.29, 669.63 and 278.25 is: 383.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.29 : 669.63 = 278.25 : x
  2. Step 2: Convert to fraction form
    485.29/669.63 = 278.25/x
  3. Step 3: Cross multiply
    485.29x = 669.63 × 278.25
  4. Step 4: Simplify right side
    485.29x = 186,323.16
  5. Step 5: Solve for x
    x = 186,323.16/485.29
  6. Step 6: Final answer
    x = 383.94

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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.