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It is shown how certain observations interpreted in the background of theFriedmann model with $\Lambda < 0 = k$ (the $\Lambda$CDM model) can bere-interpreted using the $\Lambda = 0$ Lema\^{\i}tre - Tolman (L-T) model so asto do away with the "dark energy". The purpose of the paper is to clarify theunderlying geometrical relations by doing the calculations as much as possibleanalytically or by very simple numerical programs. In the first part of thepaper (fictitious) observations of the distribution of expansion velocity alongthe past light cone of the observer are considered. It is shown that the wholepast light cone of the $\Lambda$CDM observer can be reproduced in the L-T modelwith $\Lambda = 0 = E$. This is a geometric exercise that has the advantage ofbeing free of numerical complications. In the second part, the luminositydistance - redshift relation of the $\Lambda$CDM model is duplicated using theL-T model with $-k = 2E/r^2 =$ constant $> 0$. The value of $k$ and thefunction $t_B(r)$ are determined by the $\Lambda$CDM parameters. Generalproperties of this L-T model are described. Difficulties of carrying thenumerical calculations through the apparent horizon are presented in detail andmostly solved. The second model is a counterexample to the claim that an L-Tmodel mimicking $\Lambda$CDM must contain a void around the center - it has apeak of density at $R = 0$.

Accelerating expansion or inhomogeneity? A comparison of the $\Lambda$CDM and Lema\^{\i}tre - Tolman models