Home / 1,321.64-1,981.78-618.08

Finding the Fourth Proportional to 1,321.64, 1,981.78 and 618.08

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Solution

The fourth proportional to 1,321.64, 1,981.78 and 618.08 is: 926.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.64 : 1,981.78 = 618.08 : x
  2. Step 2: Convert to fraction form
    1,321.64/1,981.78 = 618.08/x
  3. Step 3: Cross multiply
    1,321.64x = 1,981.78 × 618.08
  4. Step 4: Simplify right side
    1,321.64x = 1,224,898.58
  5. Step 5: Solve for x
    x = 1,224,898.58/1,321.64
  6. Step 6: Final answer
    x = 926.80

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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.