I. Matematikaning 5-mavzusi bo‘yicha asosiy nazariy material: ma’ruza matni Reja

Teorema (qo’shish teoremasi): Birgalikda bo’lmagan 2 hodisadan hech bo’lmaganda bittasining ro’y berish ehtimoli bu hodisalar ehtimollarining yig’indisiga teng:

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Umumiy holda, agar birgalikda bo’lmagan hodisa bolsa,

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O’zaro birgalikda bo’lgan ikkita hodisadan hech bo’lmaganda bittasining ro’y berish ehtimoli ular har birining ehtimollari yig’indisidan ularning birgalikda ro’y berish ehtimolini ayirilganiga teng:

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O’zaro bog’liq bo’lmagan hodisalar uchun ehtimollarni qo’shish formulasi:

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Namunaviy masalalar yechish

Masala: Gulzorda 20 ta qizil, 30 ta binafsha rang va 40 ta oq rangli astra ochilgan. Agar kech tushgandan so’ng bitta gul uzilgan bo’lsa, uning qizil yoki binafsha rang bo’lish ehtimolini toping.

Yechish: .

Masala: 1- va 2- to’pdan otilganda, nishonga tegish ehtimoli mos ravishda 0,7 va 0,8 ga teng. Ikkala to’pdan bir vaqtda o’q otilganda hech bo’lmaganda bittasining nishonga tegish ehtimolini toping.

Yechish: .