Home / 1,720.19-2,580.29-421.64

Finding the Fourth Proportional to 1,720.19, 2,580.29 and 421.64

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Solution

The fourth proportional to 1,720.19, 2,580.29 and 421.64 is: 632.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,720.19 : 2,580.29 = 421.64 : x
  2. Step 2: Convert to fraction form
    1,720.19/2,580.29 = 421.64/x
  3. Step 3: Cross multiply
    1,720.19x = 2,580.29 × 421.64
  4. Step 4: Simplify right side
    1,720.19x = 1,087,938.47
  5. Step 5: Solve for x
    x = 1,087,938.47/1,720.19
  6. Step 6: Final answer
    x = 632.45

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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.