Finding the Fourth Proportional to 138.21, 206.75 and 129.70
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Solution
The fourth proportional to 138.21, 206.75 and 129.70 is: 194.03
Step by Step Solution
- Step 1: Write the proportion equation
138.21 : 206.75 = 129.70 : x - Step 2: Convert to fraction form
138.21/206.75 = 129.70/x - Step 3: Cross multiply
138.21x = 206.75 × 129.70 - Step 4: Simplify right side
138.21x = 26,816.06 - Step 5: Solve for x
x = 26,816.06/138.21 - Step 6: Final answer
x = 194.03
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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.