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Finding the Fourth Proportional to 428.92, 643.44 and 368.80

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Solution

The fourth proportional to 428.92, 643.44 and 368.80 is: 553.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.92 : 643.44 = 368.80 : x
  2. Step 2: Convert to fraction form
    428.92/643.44 = 368.80/x
  3. Step 3: Cross multiply
    428.92x = 643.44 × 368.80
  4. Step 4: Simplify right side
    428.92x = 237,300.67
  5. Step 5: Solve for x
    x = 237,300.67/428.92
  6. Step 6: Final answer
    x = 553.25

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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.