\(=>Im=I1=I2=I3=I4=\dfrac{U}{RTd}=\dfrac{100}{R1+\dfrac{R1}{2}+\dfrac{R1}{3}+\dfrac{R1}{4}}\)
\(=\dfrac{100}{\dfrac{24R1+12R1+8R1+6R1}{24}}=\dfrac{2400}{50R1}\left(A\right)\)
\(=>U1=I1.R1=\dfrac{2400}{50}=48V\)
\(=>U2=I2.R2=\dfrac{2400}{50R1}.\dfrac{R1}{2}=24V\)
\(=>U3=I3.R3=\dfrac{2400}{50.3}=16V\)
\(=>U4=I4.R4=\dfrac{2400}{50.4}=12V\)