Question

[(20+339÷3+a÷4)×7-5×400]÷3-22×3+125×8=1000

Answer 1

[(20+113+a:4)x7-2000]:3-66=1000-125x8=1000-1000=0
[(133+a:4)x7-2000]:3=0+66=66
(133+a:4)x7-2000=66x3=198
(133+a:4)x7=198+2000=2198
133+a:4=2198:7=314
a:4=314-133= 181
a=181x4=   724

Answer 2

[(20+113+a/4)7-2000]:3-66+1000=1000
[(20+113+a/4)7-2000]:3-66=1000-1000
[(20+113+a/4)7-2000]:3-66=0
[(123+a/4)7-2000]:3=66
(123+a/4)7-2000=66•3
(123+a/4)7-2000=198
(123+a/4)7=198+2000
(123+a/4)7=2198
123+a/4=2198:7
123+a/4=314
a/4=314-123
a/4=191
a=191•4
a=764