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Finding the Fourth Proportional to 491.95, 678.72 and 305.37

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Solution

The fourth proportional to 491.95, 678.72 and 305.37 is: 421.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.95 : 678.72 = 305.37 : x
  2. Step 2: Convert to fraction form
    491.95/678.72 = 305.37/x
  3. Step 3: Cross multiply
    491.95x = 678.72 × 305.37
  4. Step 4: Simplify right side
    491.95x = 207,255.81
  5. Step 5: Solve for x
    x = 207,255.81/491.95
  6. Step 6: Final answer
    x = 421.30

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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.