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Finding the Fourth Proportional to 368.80, 508.76 and 221.40

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Solution

The fourth proportional to 368.80, 508.76 and 221.40 is: 305.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    368.80 : 508.76 = 221.40 : x
  2. Step 2: Convert to fraction form
    368.80/508.76 = 221.40/x
  3. Step 3: Cross multiply
    368.80x = 508.76 × 221.40
  4. Step 4: Simplify right side
    368.80x = 112,639.46
  5. Step 5: Solve for x
    x = 112,639.46/368.80
  6. Step 6: Final answer
    x = 305.42

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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.