Finding the Fourth Proportional to 428.88, 645.84 and 307.99
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Solution
The fourth proportional to 428.88, 645.84 and 307.99 is: 463.79
Step by Step Solution
- Step 1: Write the proportion equation
428.88 : 645.84 = 307.99 : x - Step 2: Convert to fraction form
428.88/645.84 = 307.99/x - Step 3: Cross multiply
428.88x = 645.84 × 307.99 - Step 4: Simplify right side
428.88x = 198,912.26 - Step 5: Solve for x
x = 198,912.26/428.88 - Step 6: Final answer
x = 463.79
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Why These Related Problems?
These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.