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Finding the Fourth Proportional to 642.98, 964.47 and 258.23

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Solution

The fourth proportional to 642.98, 964.47 and 258.23 is: 387.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.98 : 964.47 = 258.23 : x
  2. Step 2: Convert to fraction form
    642.98/964.47 = 258.23/x
  3. Step 3: Cross multiply
    642.98x = 964.47 × 258.23
  4. Step 4: Simplify right side
    642.98x = 249,055.09
  5. Step 5: Solve for x
    x = 249,055.09/642.98
  6. Step 6: Final answer
    x = 387.35

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.