Finding the Fourth Proportional to 390.34, 538.50 and 235
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Solution
The fourth proportional to 390.34, 538.50 and 235 is: 324.20
Step by Step Solution
- Step 1: Write the proportion equation
390.34 : 538.50 = 235 : x - Step 2: Convert to fraction form
390.34/538.50 = 235/x - Step 3: Cross multiply
390.34x = 538.50 × 235 - Step 4: Simplify right side
390.34x = 126,547.50 - Step 5: Solve for x
x = 126,547.50/390.34 - Step 6: Final answer
x = 324.20
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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.