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Finding the Fourth Proportional to 612.79, 919.64 and 288.39

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Solution

The fourth proportional to 612.79, 919.64 and 288.39 is: 432.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.79 : 919.64 = 288.39 : x
  2. Step 2: Convert to fraction form
    612.79/919.64 = 288.39/x
  3. Step 3: Cross multiply
    612.79x = 919.64 × 288.39
  4. Step 4: Simplify right side
    612.79x = 265,210.98
  5. Step 5: Solve for x
    x = 265,210.98/612.79
  6. Step 6: Final answer
    x = 432.79

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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.