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Finding the Fourth Proportional to 386.40, 532.80 and 288.16

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Solution

The fourth proportional to 386.40, 532.80 and 288.16 is: 397.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.40 : 532.80 = 288.16 : x
  2. Step 2: Convert to fraction form
    386.40/532.80 = 288.16/x
  3. Step 3: Cross multiply
    386.40x = 532.80 × 288.16
  4. Step 4: Simplify right side
    386.40x = 153,531.65
  5. Step 5: Solve for x
    x = 153,531.65/386.40
  6. Step 6: Final answer
    x = 397.34

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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.