Home / 1,020.09-1,407.78-621.69

Finding the Fourth Proportional to 1,020.09, 1,407.78 and 621.69

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Solution

The fourth proportional to 1,020.09, 1,407.78 and 621.69 is: 857.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,020.09 : 1,407.78 = 621.69 : x
  2. Step 2: Convert to fraction form
    1,020.09/1,407.78 = 621.69/x
  3. Step 3: Cross multiply
    1,020.09x = 1,407.78 × 621.69
  4. Step 4: Simplify right side
    1,020.09x = 875,205.39
  5. Step 5: Solve for x
    x = 875,205.39/1,020.09
  6. Step 6: Final answer
    x = 857.97

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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.