Finding the Fourth Proportional to 428.56, 643 and 223
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Solution
The fourth proportional to 428.56, 643 and 223 is: 334.58
Step by Step Solution
- Step 1: Write the proportion equation
428.56 : 643 = 223 : x - Step 2: Convert to fraction form
428.56/643 = 223/x - Step 3: Cross multiply
428.56x = 643 × 223 - Step 4: Simplify right side
428.56x = 143,389 - Step 5: Solve for x
x = 143,389/428.56 - Step 6: Final answer
x = 334.58
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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.