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Finding the Fourth Proportional to 380.91, 526.05 and 287.51

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Solution

The fourth proportional to 380.91, 526.05 and 287.51 is: 397.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.91 : 526.05 = 287.51 : x
  2. Step 2: Convert to fraction form
    380.91/526.05 = 287.51/x
  3. Step 3: Cross multiply
    380.91x = 526.05 × 287.51
  4. Step 4: Simplify right side
    380.91x = 151,242.01
  5. Step 5: Solve for x
    x = 151,242.01/380.91
  6. Step 6: Final answer
    x = 397.05

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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.