Quesrion about calculating losses in tranches: what am i doing wrong here? Because the right anwer is:

$-33\mathrm{.}3\%$ loss on mezzanine abs tranche

$-100\%$ loss on equity abs cdo

$-93\mathrm{.}3\%$ loss on mezzanine abs cdo

$-0\%$ loss on equity abs cdo

Below is my workings on how i solved it $($wrong$)$:

$1.$ Figure out the losses on underlying assets: in our case $10\%$

$2.$ Allocate loss to original senior tranche:

Senior: $0\mathrm{.}800\mathrm{.}10=8\%$

$3.$ Allocate losses to mezzanine tranche:

The mezzanine tranche has an allocation of $15\%,$ however, since it is subordinate $($waterfall payment system$),$ it only absorbs losses after the senior tranche has absorbed its $80\%$ share. Calculation: $15\%-8\%=7\%$

$4.$ Break down the mezzanine tranche into CDO tranches:

The senior CDO tranche: $0\mathrm{.}657\%=4\mathrm{.}55$

The mezzanine tranche: $0\mathrm{.}257\%=1\mathrm{.}75$

The equity tranche: $7\%-4\mathrm{.}55\%-1\mathrm{.}75\%=0\mathrm{.}7\%($or $0\mathrm{.}17\%=0\mathrm{.}7\%)$