Home / 1,214.80-1,821.79-392.88

Finding the Fourth Proportional to 1,214.80, 1,821.79 and 392.88

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Solution

The fourth proportional to 1,214.80, 1,821.79 and 392.88 is: 589.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,214.80 : 1,821.79 = 392.88 : x
  2. Step 2: Convert to fraction form
    1,214.80/1,821.79 = 392.88/x
  3. Step 3: Cross multiply
    1,214.80x = 1,821.79 × 392.88
  4. Step 4: Simplify right side
    1,214.80x = 715,752.18
  5. Step 5: Solve for x
    x = 715,752.18/1,214.80
  6. Step 6: Final answer
    x = 589.19

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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.