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Finding the Fourth Proportional to 428.08, 645.67 and 377.35

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Solution

The fourth proportional to 428.08, 645.67 and 377.35 is: 569.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.08 : 645.67 = 377.35 : x
  2. Step 2: Convert to fraction form
    428.08/645.67 = 377.35/x
  3. Step 3: Cross multiply
    428.08x = 645.67 × 377.35
  4. Step 4: Simplify right side
    428.08x = 243,643.57
  5. Step 5: Solve for x
    x = 243,643.57/428.08
  6. Step 6: Final answer
    x = 569.16

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.