Let's Get Serious by Jermaine Jackson first appeared on the Israeli foreign-music chart on 23 Jun 1980, entering at #25. It peaked at #10 on 21 Jul 1980. In total it spent 8 weeks on the chart, last charting on 11 Aug 1980.
| Wk | Date | Pos |
|---|---|---|
| 1 | 23 Jun 1980 | 25 |
| 2 | 30 Jun 1980 | 19 |
| 3 | 7 Jul 1980 | 14 |
| 4 | 14 Jul 1980 | 11 |
| 5 | 21 Jul 1980 | 10 |
| 6 | 28 Jul 1980 | 17 |
| 7 | 4 Aug 1980 | 30 |
| 8 | 11 Aug 1980 | 35 |