Mixed Format $$E _ { L D N E } = \sqrt { E _R ^ { 2 } + E _X ^ { 2 } }$$

Mixed format: $$E _ { L D N E } = \sqrt { E _R ^ { 2 } + E _X ^ { 2 } }$$ (with a space between the whole number and the numerator) Fraction format: $1 /4$
Reduce all fractions. In estimating a job, it is decided that it should take 13 people $\begin{array} { l } I = P / E \\C M = K N L I / E _ { e }\end{array}$ hours each to do part of the work, and 7 people $6~~3 / 4$ hours each to do the remainder of the job. Determine the total number of hours estimated for the job.