Home / 1,380.40-2,070.63-406.58

Finding the Fourth Proportional to 1,380.40, 2,070.63 and 406.58

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Solution

The fourth proportional to 1,380.40, 2,070.63 and 406.58 is: 609.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380.40 : 2,070.63 = 406.58 : x
  2. Step 2: Convert to fraction form
    1,380.40/2,070.63 = 406.58/x
  3. Step 3: Cross multiply
    1,380.40x = 2,070.63 × 406.58
  4. Step 4: Simplify right side
    1,380.40x = 841,866.39
  5. Step 5: Solve for x
    x = 841,866.39/1,380.40
  6. Step 6: Final answer
    x = 609.87

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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.