Finding the Fourth Proportional to 390.99, 539.43 and 235.65
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Solution
The fourth proportional to 390.99, 539.43 and 235.65 is: 325.11
Step by Step Solution
- Step 1: Write the proportion equation
390.99 : 539.43 = 235.65 : x - Step 2: Convert to fraction form
390.99/539.43 = 235.65/x - Step 3: Cross multiply
390.99x = 539.43 × 235.65 - Step 4: Simplify right side
390.99x = 127,116.68 - Step 5: Solve for x
x = 127,116.68/390.99 - Step 6: Final answer
x = 325.11
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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.