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Finding the Fourth Proportional to 420.16, 579.40 and 272.80

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Solution

The fourth proportional to 420.16, 579.40 and 272.80 is: 376.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.16 : 579.40 = 272.80 : x
  2. Step 2: Convert to fraction form
    420.16/579.40 = 272.80/x
  3. Step 3: Cross multiply
    420.16x = 579.40 × 272.80
  4. Step 4: Simplify right side
    420.16x = 158,060.32
  5. Step 5: Solve for x
    x = 158,060.32/420.16
  6. Step 6: Final answer
    x = 376.19

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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.