Home / 1,430.13-2,145.21-780.75

Finding the Fourth Proportional to 1,430.13, 2,145.21 and 780.75

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Solution

The fourth proportional to 1,430.13, 2,145.21 and 780.75 is: 1,171.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,430.13 : 2,145.21 = 780.75 : x
  2. Step 2: Convert to fraction form
    1,430.13/2,145.21 = 780.75/x
  3. Step 3: Cross multiply
    1,430.13x = 2,145.21 × 780.75
  4. Step 4: Simplify right side
    1,430.13x = 1,674,872.71
  5. Step 5: Solve for x
    x = 1,674,872.71/1,430.13
  6. Step 6: Final answer
    x = 1,171.13

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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.