Finding the Fourth Proportional to 138.36, 207.58 and 69.84
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Solution
The fourth proportional to 138.36, 207.58 and 69.84 is: 104.78
Step by Step Solution
- Step 1: Write the proportion equation
138.36 : 207.58 = 69.84 : x - Step 2: Convert to fraction form
138.36/207.58 = 69.84/x - Step 3: Cross multiply
138.36x = 207.58 × 69.84 - Step 4: Simplify right side
138.36x = 14,497.39 - Step 5: Solve for x
x = 14,497.39/138.36 - Step 6: Final answer
x = 104.78
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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.