Home / 205.72-309.73-142

Finding the Fourth Proportional to 205.72, 309.73 and 142

Calculator

Solution

The fourth proportional to 205.72, 309.73 and 142 is: 213.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.72 : 309.73 = 142 : x
  2. Step 2: Convert to fraction form
    205.72/309.73 = 142/x
  3. Step 3: Cross multiply
    205.72x = 309.73 × 142
  4. Step 4: Simplify right side
    205.72x = 43,981.66
  5. Step 5: Solve for x
    x = 43,981.66/205.72
  6. Step 6: Final answer
    x = 213.79

Related Problems

Find fourth proportional to 102.86, 154.87 and 71
Half scale
Find fourth proportional to 411.44, 619.46 and 284
Double scale
Find fourth proportional to 206.72, 311.24 and 143
Similar ratio
Find fourth proportional to 308.58, 464.60 and 213
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.