Home / 6,420.40-9,630.76-1,978.16

Finding the Fourth Proportional to 6,420.40, 9,630.76 and 1,978.16

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Solution

The fourth proportional to 6,420.40, 9,630.76 and 1,978.16 is: 2,967.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    6,420.40 : 9,630.76 = 1,978.16 : x
  2. Step 2: Convert to fraction form
    6,420.40/9,630.76 = 1,978.16/x
  3. Step 3: Cross multiply
    6,420.40x = 9,630.76 × 1,978.16
  4. Step 4: Simplify right side
    6,420.40x = 19,051,184.20
  5. Step 5: Solve for x
    x = 19,051,184.20/6,420.40
  6. Step 6: Final answer
    x = 2,967.29

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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.