Finding the Fourth Proportional to 139.32, 208.78 and 98.75
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Solution
The fourth proportional to 139.32, 208.78 and 98.75 is: 147.99
Step by Step Solution
- Step 1: Write the proportion equation
139.32 : 208.78 = 98.75 : x - Step 2: Convert to fraction form
139.32/208.78 = 98.75/x - Step 3: Cross multiply
139.32x = 208.78 × 98.75 - Step 4: Simplify right side
139.32x = 20,617.30 - Step 5: Solve for x
x = 20,617.30/139.32 - Step 6: Final answer
x = 147.99
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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.