Home / 1,220.32-1,828.86-780.76

Finding the Fourth Proportional to 1,220.32, 1,828.86 and 780.76

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Solution

The fourth proportional to 1,220.32, 1,828.86 and 780.76 is: 1,170.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.32 : 1,828.86 = 780.76 : x
  2. Step 2: Convert to fraction form
    1,220.32/1,828.86 = 780.76/x
  3. Step 3: Cross multiply
    1,220.32x = 1,828.86 × 780.76
  4. Step 4: Simplify right side
    1,220.32x = 1,427,900.73
  5. Step 5: Solve for x
    x = 1,427,900.73/1,220.32
  6. Step 6: Final answer
    x = 1,170.10

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1.5x scale

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.