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Finding the Fourth Proportional to 400.77, 555.63 and 378.90

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Solution

The fourth proportional to 400.77, 555.63 and 378.90 is: 525.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.77 : 555.63 = 378.90 : x
  2. Step 2: Convert to fraction form
    400.77/555.63 = 378.90/x
  3. Step 3: Cross multiply
    400.77x = 555.63 × 378.90
  4. Step 4: Simplify right side
    400.77x = 210,528.21
  5. Step 5: Solve for x
    x = 210,528.21/400.77
  6. Step 6: Final answer
    x = 525.31

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Find fourth proportional to 200.39, 277.82 and 189.45
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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.