Question

3. The number of seven digit integers, with sum of the digits equal to 10 and formed by using the digits 1,2 and 3 only, is (2009) A) 55 B) 66 C) 77 D) 88

IIT/JEE

Maths

Solution

248

4.0 (1 ratings)

Hus possitilitivs an ( (1) operatorname{ll} 1123 Rightarrow frac{7 !}{5 ! times 1 ! times 1 !}=42 ) ( (i i) 1111222=frac{71}{41,31}=35 ) ( 10+a=42+35=77 ) ure