Notice pay implies that the employee shall attend the duties for the Notice Period, if due to any reasons he is not able to do so , upon mutual agreement the short notice period can be compensated against cash equivalent.
In this case only 20 days salary is to be paid. If you pay for 30 days the there will be no adjustment against 10 short days.
99 98 97 10 65
6th March 2019 From India, Mumbai
Both under Shop & Estd Act and under Factories Act, unused ELs can not be adjusted against the notice period. If the notice was 30 days and the employee only worked for 20 days and has 10 unused EL, then you need to reduce the pending notice of 10 days from his earnings of 20 days and add 10 days of Leave encashment.
8th March 2019 From India, Delhi