Home / 1,282.40-1,921.80-631.70

Finding the Fourth Proportional to 1,282.40, 1,921.80 and 631.70

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Solution

The fourth proportional to 1,282.40, 1,921.80 and 631.70 is: 946.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,282.40 : 1,921.80 = 631.70 : x
  2. Step 2: Convert to fraction form
    1,282.40/1,921.80 = 631.70/x
  3. Step 3: Cross multiply
    1,282.40x = 1,921.80 × 631.70
  4. Step 4: Simplify right side
    1,282.40x = 1,214,001.06
  5. Step 5: Solve for x
    x = 1,214,001.06/1,282.40
  6. Step 6: Final answer
    x = 946.66

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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.