5. The answers to the three calculations below are to be written in descending order.
$$
\begin{array}{cl}
X & 0.6 \times 0.5+0.4 \\
Y & 0.6 \times 0.5 \div 0.4 \\
Z & 0.6 \times 0.5 \times 0.4
\end{array}
$$

What is the correct order?
A $Y Z X$
B $X Y Z$
C $X Z Y$
D $Y X Z$
E $Z Y X$
5. D The answers to the three calculations are as follows:
$$
\begin{array}{ll}
X & 0.6 \times 0.5+0.4=0.3+0.4=0.7 ; \\
Y & 0.6 \times 0.5 \div 0.4=0.3 \div 0.4=3 \div 4=0.75 ; \\
Z & 0.6 \times 0.5 \times 0.4=0.3 \times 0.4=0.12
\end{array}
$$

So the correct order is $Y X Z$.