Помогите решить уравнения с записими (16m+5m): 18=4 (17 n-8 n)*13=351

(16m+5m): 18=4 21m: 18=421m=4*1821m=72m=72:21m=3 9/21 ili 3 3/7_________________________ (16m+5m): 18=4 21m: 18=4 21*3 3/7:18=4 21*24/7:18=4 3*24:18=4 72:18=4 4=4 (17 n-8 n)*13=351 9n*13=351 9n=351:13 9n=27 n=27:9 n=3