Home / 117.65-161.90-89.91

Finding the Fourth Proportional to 117.65, 161.90 and 89.91

Calculator

Solution

The fourth proportional to 117.65, 161.90 and 89.91 is: 123.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    117.65 : 161.90 = 89.91 : x
  2. Step 2: Convert to fraction form
    117.65/161.90 = 89.91/x
  3. Step 3: Cross multiply
    117.65x = 161.90 × 89.91
  4. Step 4: Simplify right side
    117.65x = 14,556.32
  5. Step 5: Solve for x
    x = 14,556.32/117.65
  6. Step 6: Final answer
    x = 123.72

Related Problems

Find fourth proportional to 58.83, 80.95 and 44.96
Half scale
Find fourth proportional to 235.31, 323.80 and 179.82
Double scale
Find fourth proportional to 118.65, 163.27 and 90.91
Similar ratio
Find fourth proportional to 176.48, 242.85 and 134.87
1.5x scale

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.