Difference between pure tone and speech audiometer

Speech audiometry was performed on 15 children with secretory otitis media pre-and post-operatively and the findings compared with the pre-and post-operative pure tone audiograms. The results showed that in 30 per cent of cases pre-operatively the speech audiogram suggested a significantly worse hearing ability than that suggested by the pure tone audiogram (PTA). Where a PTA gives a borderline threshold disproportionate parental concern should be taken seriously as the hearing ability may well be worse than the PTA suggests.

answer; i believe its echoic memory,it is believed to last three to four seconds; good luck

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)