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Finding the Fourth Proportional to 608.40, 838.75 and 421.57

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Solution

The fourth proportional to 608.40, 838.75 and 421.57 is: 581.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.40 : 838.75 = 421.57 : x
  2. Step 2: Convert to fraction form
    608.40/838.75 = 421.57/x
  3. Step 3: Cross multiply
    608.40x = 838.75 × 421.57
  4. Step 4: Simplify right side
    608.40x = 353,590.26
  5. Step 5: Solve for x
    x = 353,590.26/608.40
  6. Step 6: Final answer
    x = 581.18

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.