Home / 1,280.32-1,921.02-631.78

Finding the Fourth Proportional to 1,280.32, 1,921.02 and 631.78

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Solution

The fourth proportional to 1,280.32, 1,921.02 and 631.78 is: 947.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.32 : 1,921.02 = 631.78 : x
  2. Step 2: Convert to fraction form
    1,280.32/1,921.02 = 631.78/x
  3. Step 3: Cross multiply
    1,280.32x = 1,921.02 × 631.78
  4. Step 4: Simplify right side
    1,280.32x = 1,213,662.02
  5. Step 5: Solve for x
    x = 1,213,662.02/1,280.32
  6. Step 6: Final answer
    x = 947.94

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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.