Finding the Fourth Proportional to 428.99, 644.09 and 409.41
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Solution
The fourth proportional to 428.99, 644.09 and 409.41 is: 614.69
Step by Step Solution
- Step 1: Write the proportion equation
428.99 : 644.09 = 409.41 : x - Step 2: Convert to fraction form
428.99/644.09 = 409.41/x - Step 3: Cross multiply
428.99x = 644.09 × 409.41 - Step 4: Simplify right side
428.99x = 263,694.84 - Step 5: Solve for x
x = 263,694.84/428.99 - Step 6: Final answer
x = 614.69
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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.