Finding the Fourth Proportional to 138.12, 207.19 and 69.63
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Solution
The fourth proportional to 138.12, 207.19 and 69.63 is: 104.45
Step by Step Solution
- Step 1: Write the proportion equation
138.12 : 207.19 = 69.63 : x - Step 2: Convert to fraction form
138.12/207.19 = 69.63/x - Step 3: Cross multiply
138.12x = 207.19 × 69.63 - Step 4: Simplify right side
138.12x = 14,426.64 - Step 5: Solve for x
x = 14,426.64/138.12 - Step 6: Final answer
x = 104.45
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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.