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Finding the Fourth Proportional to 485.60, 669.87 and 288.77

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Solution

The fourth proportional to 485.60, 669.87 and 288.77 is: 398.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.60 : 669.87 = 288.77 : x
  2. Step 2: Convert to fraction form
    485.60/669.87 = 288.77/x
  3. Step 3: Cross multiply
    485.60x = 669.87 × 288.77
  4. Step 4: Simplify right side
    485.60x = 193,435.01
  5. Step 5: Solve for x
    x = 193,435.01/485.60
  6. Step 6: Final answer
    x = 398.35

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Find fourth proportional to 242.80, 334.94 and 144.38
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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.