quality control

Question 2 (Soalan 21 (a) 35 components were subjected to reliability testing for 22 hours. 3 components failed after 3, 7 and 12 hours respectively. The remaining components continued functioning until the 22 hours was up. Calculate the failure rate of these components. [35 komponen dikenakan ujian keboleharapan selama 22 jam. 3 komponen gagal selepas 3. 7 dan 12 jam masing-masing. Komponen selebihnya berfungsi sehingga tamat tempoh 22 jam. Kirakan kadar kegagalan komponen-komponen ini.) (2 Marks/ markah) (b) Five components were tested to failure. These components failed after 1, 10, 14, 17 and 23 hours respectively. Calculate the failure rate of these components. [Lima komponen dikenakan ujian keboleharapan sehingga gagal. Komponen-komponen ini gagal selepas 1, 10, 14, 17 dan 23 jam masing-masing. Kirakan kadar kegagalan komponen-komponen ini.] (2 Marks/ markah) (c) 42 components were tested for 4 hours. 5 components failed but were replaced with new components to resume testing. Calculate the failure rate of these components. [42 komponen dikenakan ujian keboleharapan selama 4 jam. 5 komponen gagal tetapi digantikan dengan komponen baru untuk meneruskan ujian. Kirakan kadar kegagalan komponen-komponen ini.) (2 Marks/ markah) (d) The failure distribution of a product can be approximated using a Weibull distribution with a slope of 3.1 and a mean life of 90 hours. Calculate the reliability at [Taburan kegagalan suatu produk boleh dianggarkan menggunakan taburan Weibull dengan kecerunan 3.1 dan hayat purata a5p2 jam. Kirakan keboleharapan pada (1) 125 hours and 125 jam dan (ii) (ii) 143 hours 143 jam. (4 Marks/ markah)