ANSWER:
1568.63
Explanation:
We have that the simple inteters formula is the following:
![I=Prt](https://img.qammunity.org/2023/formulas/mathematics/high-school/a5nwangmzhq6g687nv4jxotr6htl4awojj.png)
Where I is the interest earned, P is the principal, that is, the amount invested, r the rate and t the time. We substitute and calculate for P, like this:
![\begin{gathered} r=4(1)/(4)\text{\%}=4.25\text{\%}=(4.25)/(100)=0.0425 \\ t=6 \\ I=400 \\ \text{ replacing} \\ 400=P\cdot0.0425\cdot6 \\ P=(400)/(6\cdot0.425) \\ P=1568.63 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/aggnzl42mqw2h7yjdpk7mvh7uggv0310u7.png)
Therefore, for a profit of 400 under these conditions, 1568.63 must be invested