Question

(7^4+2×7^5+3×7^6):126=

Answer 1

(7^4+2×7^5+3×7^6):126=
=(1+2*7+3*7^2)*7^4:126 = 
= (1+14+3*49)*2401:126 = 
= (1+14+147)*2401:126 = 
= 162*2401 :126 = 
= 3087

Answer 2

(7⁴+2×7⁵+3×7⁶):126=
=7⁴·(1+2·7+3·7²):12
=2401·(1+14+3·49):126
=162·2401:126
=388962:126
=3087