Finding the Fourth Proportional to 138.14, 207.08 and 86.63
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Solution
The fourth proportional to 138.14, 207.08 and 86.63 is: 129.86
Step by Step Solution
- Step 1: Write the proportion equation
138.14 : 207.08 = 86.63 : x - Step 2: Convert to fraction form
138.14/207.08 = 86.63/x - Step 3: Cross multiply
138.14x = 207.08 × 86.63 - Step 4: Simplify right side
138.14x = 17,938.59 - Step 5: Solve for x
x = 17,938.59/138.14 - Step 6: Final answer
x = 129.86
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.