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Finding the Fourth Proportional to 690.89, 947.79 and 670.08

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Solution

The fourth proportional to 690.89, 947.79 and 670.08 is: 919.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.89 : 947.79 = 670.08 : x
  2. Step 2: Convert to fraction form
    690.89/947.79 = 670.08/x
  3. Step 3: Cross multiply
    690.89x = 947.79 × 670.08
  4. Step 4: Simplify right side
    690.89x = 635,095.12
  5. Step 5: Solve for x
    x = 635,095.12/690.89
  6. Step 6: Final answer
    x = 919.24

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.