Two elementary algebra word problems are presented which have answers helpful enough in the derivation of the effects of special relativity that little else need be added in this derivation. The two problems are entirely in the classical setting before any reference is made to relativistic assumptions. The chance for confusion related to relativistic assumption is thus extracted and concentrated into a very short and direct part of the derivations for the contraction of lengths, retardation of time, and nonsynchronization of clocks. Thus these effects of the constancy of the speed of light follow immediately and directly from the assumption of the constancy of this speed in a way which elucidates the logical connection between the assumption and the effects.