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Finding the Fourth Proportional to 688.94, 950.51 and 390.15

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Solution

The fourth proportional to 688.94, 950.51 and 390.15 is: 538.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.94 : 950.51 = 390.15 : x
  2. Step 2: Convert to fraction form
    688.94/950.51 = 390.15/x
  3. Step 3: Cross multiply
    688.94x = 950.51 × 390.15
  4. Step 4: Simplify right side
    688.94x = 370,841.48
  5. Step 5: Solve for x
    x = 370,841.48/688.94
  6. Step 6: Final answer
    x = 538.28

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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.