Home / 1,280.48-1,920.80-631.36

Finding the Fourth Proportional to 1,280.48, 1,920.80 and 631.36

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Solution

The fourth proportional to 1,280.48, 1,920.80 and 631.36 is: 947.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.48 : 1,920.80 = 631.36 : x
  2. Step 2: Convert to fraction form
    1,280.48/1,920.80 = 631.36/x
  3. Step 3: Cross multiply
    1,280.48x = 1,920.80 × 631.36
  4. Step 4: Simplify right side
    1,280.48x = 1,212,716.29
  5. Step 5: Solve for x
    x = 1,212,716.29/1,280.48
  6. Step 6: Final answer
    x = 947.08

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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.