Question

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

# 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

Solution