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Finding the Fourth Proportional to 623.45, 860.01 and 390.71

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Solution

The fourth proportional to 623.45, 860.01 and 390.71 is: 538.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    623.45 : 860.01 = 390.71 : x
  2. Step 2: Convert to fraction form
    623.45/860.01 = 390.71/x
  3. Step 3: Cross multiply
    623.45x = 860.01 × 390.71
  4. Step 4: Simplify right side
    623.45x = 336,014.51
  5. Step 5: Solve for x
    x = 336,014.51/623.45
  6. Step 6: Final answer
    x = 538.96

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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.