Home / 1,020.20-1,407.98-621.88

Finding the Fourth Proportional to 1,020.20, 1,407.98 and 621.88

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Solution

The fourth proportional to 1,020.20, 1,407.98 and 621.88 is: 858.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,020.20 : 1,407.98 = 621.88 : x
  2. Step 2: Convert to fraction form
    1,020.20/1,407.98 = 621.88/x
  3. Step 3: Cross multiply
    1,020.20x = 1,407.98 × 621.88
  4. Step 4: Simplify right side
    1,020.20x = 875,592.64
  5. Step 5: Solve for x
    x = 875,592.64/1,020.20
  6. Step 6: Final answer
    x = 858.26

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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.