Compute the normal stress

Consider the I-beam cross-section:

The table below has the geometric properties for different specifications for a steel beam:

Designation h (in) w (in) Ix (in^4) Iy (in^4)
S24 x 100 24 7.425 2,390 47.7
S24 x 90 24 7.125 2,250 44.9
S24 x 80 24 7 2,100 42.2
S20 x 96 20.3 7.2 1,670 50.2
S20 x 86 20.3 7.06 1,580 46.8
S20 x 75 20 6.385 1,280 29.8
S20 x 66 20 6.255 1,190 27.7
S18 x 70 18 6.251 926 24.1
S18 x 54.7 18 6.001 804 20.8
S15 x 50 15 5.64 486 15.7

For the beam designations indicated below, determine the maximum normal stress $\sigma_x$ assuming that the maximum moment is equal to $M_{max} = 4 \times 10^5 \rm\ lb \cdot in$.

Designation $\sigma_x$
S24 x 90
S18 x 54.7
S24 x 80
S18 x 70

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Compute the normal stress

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Started at:
2026-08-04 22:47:26 (CDT)
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{
  "sigma1": 2.1333333333333333,
  "sigma2": 4.477611940298507,
  "sigma3": 2.2857142857142856,
  "sigma4": 3.8876889848812093
}
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