Finding the Fourth Proportional to 405.21, 559.08 and 257.79
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Solution
The fourth proportional to 405.21, 559.08 and 257.79 is: 355.68
Step by Step Solution
- Step 1: Write the proportion equation
405.21 : 559.08 = 257.79 : x - Step 2: Convert to fraction form
405.21/559.08 = 257.79/x - Step 3: Cross multiply
405.21x = 559.08 × 257.79 - Step 4: Simplify right side
405.21x = 144,125.23 - Step 5: Solve for x
x = 144,125.23/405.21 - Step 6: Final answer
x = 355.68
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.