In this lesson let’s learn about application of order of expressions. So, real life examples, it says Hank Aaron’s last season in the Major League Baseball was in 1976. A player’s total number of bases can be found using the expression, s+2d+3d+4h, that’s singles plus 2 for every double base hit, three for every triple base hit and 4 for every home run. Use the table to find Hank Aaron’s total bases from 1976. So it says Hank hits 44 singles, eight doubles, zero triples and 10 home runs. So, first let’s substitute these values in there, so the expression given to us is s+2(d)+3(t)+4(h), so instead of s, what do I substitute? 44, plus 2(d) which is 8 plus three times zero plus 4 times 10. Now I've got addition operations and multiplication operations. In order of expressions we have to multiply first. So that’s 44 + (2)8 is 16, 3(0) is 0 + 4(10) is 40. So we multiply it first. What do I get? And then we add from left to right. 44+16 is 60+0+40, 60+40is 100. All right, so the answer, how many base hits did he have, total bases, is 100. And we did that by simply substituting the values and then following the order of operations, multiply before you add.