The expression that is equivalent to 0.40a is 
<h3>What are equivalent expressions?</h3>
Equivalent expressions are expressions that have equal values, when evaluated or simplified
The expression is given as:
0.40a
Rewrite the above expression as a fraction

Simplify the fraction

Hence, an equivalent expression of 0.4a is 
Read more about equivalent expressions at:
brainly.com/question/2972832