Betty paid 6 x $2.5 = $<<6*2.5=15>>15 for the slippers.
She paid 4 x $1.25 = $<<4*1.25=5>>5 for the lipsticks.
She paid 8 x $3 = $<<8*3=24>>24 for the hair color.
Therefore, Betty paid $15 + $5 + $24 = $<<15+5+24=44>>44 in total.
#### 44