Question

A 3-digit number 4a3 is added to another 3-digit number 984 to give a 4-digit number 13b7, which is divisible by 11. Then, (a +



b.= ?

Answer 1

Step-by-step explanation:

if we add 4a3 to 984, the sum should be 13b7.

we have options for 'a' from 0 to 9, but if we put a =2, the addition will result in

483

+ 984

1407

but the given no. is less than 1407, hence now we have two options for 'a', i.e 0 or 1

if we put a = 0, we get

403

+ 984

1387

but another condition is given, that number should be divisible by 11,

since 1387 is not divisible by 11, so a=0 cannot be a answer. now if we put a=1,

we get.

413

+ 984

1397

1397 is divisible by 11, hence a =1 & b= 9

so a + b = 1+ 9 = 10