## Task 5 - 020525

On a straight line, consecutively mark the segments $A B=3 \mathrm{~cm}, B C=5 \mathrm{~cm}$ and $C D=4 \mathrm{~cm}$! How large is the distance between the midpoints of the segments $A B$ and $C D$? Justify your answer by calculation!
The distance between $M_{A B}$ and $M_{C D}$ is derived from the length of segment $B C$ and half the lengths of segments $A B$ and $C D$, i.e.,

$$
M_{A B} M_{C D}=0.5 \cdot A B + B C + 0.5 \cdot C D = 0.5 \cdot 3 \text{~cm} + 5 \text{~cm} + 0.5 \cdot 4 \text{~cm} = 8.5 \text{~cm}
$$