Four smallest positive solutions correct equation

Question

posted this question earlier and it won't let me reply to anyone. here is the correct question

Solve for the four smallest positive solutions

Answer 1

5(sin 3πx) = 4

sin 3πx = 0.8

π3x ≈ 0.927295218^r

πx ≈ 0.309098406^r

x ≈ 0.098389078^r