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Finding the Fourth Proportional to 491.05, 678.03 and 380.35

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Solution

The fourth proportional to 491.05, 678.03 and 380.35 is: 525.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.05 : 678.03 = 380.35 : x
  2. Step 2: Convert to fraction form
    491.05/678.03 = 380.35/x
  3. Step 3: Cross multiply
    491.05x = 678.03 × 380.35
  4. Step 4: Simplify right side
    491.05x = 257,888.71
  5. Step 5: Solve for x
    x = 257,888.71/491.05
  6. Step 6: Final answer
    x = 525.18

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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.