interpretation of V$SESSION_EVENT statistics

When looking at results from v$SESSION_EVENT, I found that the value of Average_Wait for "db file scattered read" is 5-6 times higher than the Average_Wait for "db file sequential read". My understanding is that "db file scattered read" corresponds to full table scans
and "db file sequential read" corresponds to index scans/tables accesses via ROWID.
Does it really mean that full table scans are so slow?

Thanks,
Sev

Some info on the system:
Oracle 7.3.2 on HP-UX 10.20
HP 9000 K Series, 10 CPUs, 2GB RAM
300GB database on raw devices (EMC frames) db_block_size=8K, db_file_multiblock_read_count=8 We are running Oracle Financials (GL, AP, PO, FA), quite often CPU usage is at 100% (from sar -u) Received on Mon Sep 13 1999 - 02:46:06 CDT