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Finding the Fourth Proportional to 630.90, 870.30 and 456.30

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Solution

The fourth proportional to 630.90, 870.30 and 456.30 is: 629.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.90 : 870.30 = 456.30 : x
  2. Step 2: Convert to fraction form
    630.90/870.30 = 456.30/x
  3. Step 3: Cross multiply
    630.90x = 870.30 × 456.30
  4. Step 4: Simplify right side
    630.90x = 397,117.89
  5. Step 5: Solve for x
    x = 397,117.89/630.90
  6. Step 6: Final answer
    x = 629.45

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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.