Home / 1,219.17-1,831.80-780.60

Finding the Fourth Proportional to 1,219.17, 1,831.80 and 780.60

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Solution

The fourth proportional to 1,219.17, 1,831.80 and 780.60 is: 1,172.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,219.17 : 1,831.80 = 780.60 : x
  2. Step 2: Convert to fraction form
    1,219.17/1,831.80 = 780.60/x
  3. Step 3: Cross multiply
    1,219.17x = 1,831.80 × 780.60
  4. Step 4: Simplify right side
    1,219.17x = 1,429,903.08
  5. Step 5: Solve for x
    x = 1,429,903.08/1,219.17
  6. Step 6: Final answer
    x = 1,172.85

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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.