Solve the equation 21x + 27 = 300 using systematic trials. Explain each step.

2 answers

21x + 27 = 300

21x = 300 - 27 = 273

x = 300/21 = 14.3
21x + 27 = 300
21*10 + 27 = 237 -- too small
21*20 + 27 = 447 -- too big
21*15 + 27 = 342 - too big
21*14 + 27 = 321 -- too small
21*13 + 27 = 300