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Finding the Fourth Proportional to 623.90, 860.63 and 390.62

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Solution

The fourth proportional to 623.90, 860.63 and 390.62 is: 538.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    623.90 : 860.63 = 390.62 : x
  2. Step 2: Convert to fraction form
    623.90/860.63 = 390.62/x
  3. Step 3: Cross multiply
    623.90x = 860.63 × 390.62
  4. Step 4: Simplify right side
    623.90x = 336,179.29
  5. Step 5: Solve for x
    x = 336,179.29/623.90
  6. Step 6: Final answer
    x = 538.84

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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.