Finding the Fourth Proportional to 1,439, 2,158.86 and 413
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Solution
The fourth proportional to 1,439, 2,158.86 and 413 is: 619.60
Step by Step Solution
- Step 1: Write the proportion equation
1,439 : 2,158.86 = 413 : x - Step 2: Convert to fraction form
1,439/2,158.86 = 413/x - Step 3: Cross multiply
1,439x = 2,158.86 × 413 - Step 4: Simplify right side
1,439x = 891,609.18 - Step 5: Solve for x
x = 891,609.18/1,439 - Step 6: Final answer
x = 619.60
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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.