Finding the Fourth Proportional to 138.70, 191.36 and 79.66
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Solution
The fourth proportional to 138.70, 191.36 and 79.66 is: 109.90
Step by Step Solution
- Step 1: Write the proportion equation
138.70 : 191.36 = 79.66 : x - Step 2: Convert to fraction form
138.70/191.36 = 79.66/x - Step 3: Cross multiply
138.70x = 191.36 × 79.66 - Step 4: Simplify right side
138.70x = 15,243.74 - Step 5: Solve for x
x = 15,243.74/138.70 - Step 6: Final answer
x = 109.90
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.