Home / 253.07-379.78-90.75

Finding the Fourth Proportional to 253.07, 379.78 and 90.75

Calculator

Solution

The fourth proportional to 253.07, 379.78 and 90.75 is: 136.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.07 : 379.78 = 90.75 : x
  2. Step 2: Convert to fraction form
    253.07/379.78 = 90.75/x
  3. Step 3: Cross multiply
    253.07x = 379.78 × 90.75
  4. Step 4: Simplify right side
    253.07x = 34,465.04
  5. Step 5: Solve for x
    x = 34,465.04/253.07
  6. Step 6: Final answer
    x = 136.19

Related Problems

Find fourth proportional to 126.54, 189.89 and 45.38
Half scale
Find fourth proportional to 506.14, 759.56 and 181.50
Double scale
Find fourth proportional to 254.07, 381.28 and 91.75
Similar ratio
Find fourth proportional to 379.61, 569.67 and 136.13
1.5x scale

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.