Home / 1,038.20-1,556.55-421.60

Finding the Fourth Proportional to 1,038.20, 1,556.55 and 421.60

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Solution

The fourth proportional to 1,038.20, 1,556.55 and 421.60 is: 632.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,038.20 : 1,556.55 = 421.60 : x
  2. Step 2: Convert to fraction form
    1,038.20/1,556.55 = 421.60/x
  3. Step 3: Cross multiply
    1,038.20x = 1,556.55 × 421.60
  4. Step 4: Simplify right side
    1,038.20x = 656,241.48
  5. Step 5: Solve for x
    x = 656,241.48/1,038.20
  6. Step 6: Final answer
    x = 632.10

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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.