Home / 1,620.40-2,431.20-646.24

Finding the Fourth Proportional to 1,620.40, 2,431.20 and 646.24

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Solution

The fourth proportional to 1,620.40, 2,431.20 and 646.24 is: 969.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,620.40 : 2,431.20 = 646.24 : x
  2. Step 2: Convert to fraction form
    1,620.40/2,431.20 = 646.24/x
  3. Step 3: Cross multiply
    1,620.40x = 2,431.20 × 646.24
  4. Step 4: Simplify right side
    1,620.40x = 1,571,138.69
  5. Step 5: Solve for x
    x = 1,571,138.69/1,620.40
  6. Step 6: Final answer
    x = 969.60

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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.