Home / 253.65-380.55-80.35

Finding the Fourth Proportional to 253.65, 380.55 and 80.35

Calculator

Solution

The fourth proportional to 253.65, 380.55 and 80.35 is: 120.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.65 : 380.55 = 80.35 : x
  2. Step 2: Convert to fraction form
    253.65/380.55 = 80.35/x
  3. Step 3: Cross multiply
    253.65x = 380.55 × 80.35
  4. Step 4: Simplify right side
    253.65x = 30,577.19
  5. Step 5: Solve for x
    x = 30,577.19/253.65
  6. Step 6: Final answer
    x = 120.55

Related Problems

Find fourth proportional to 126.83, 190.28 and 40.18
Half scale
Find fourth proportional to 507.30, 761.10 and 160.70
Double scale
Find fourth proportional to 254.65, 382.05 and 81.35
Similar ratio
Find fourth proportional to 380.48, 570.83 and 120.53
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.