17. Subtraction. According to the order of operations, he should've done the exponent of 3 first.
18. He then did 15×2. According to the order of operations, he should've done the multiplication of 8×2, since, if there are only multiplication and/or division left, you work left to right. He isn't correct.
19. 16, I think, I did it in my head.
The answer would be:
93
+75
-------
168
Answer:(6 7/10)/(1/14)
(67/10)/(1/14)
(67/10)*(14/1)
938/10
(930+8)/10
93+8/10
93 4/5
Step-by-step explanation:
Answer is in the attachment below.
The quotient of -1 4/5 and 3 1/4 = (<span>-1 4/5) / ( 3 1/4)
= [ - (5 * 1 + 4) / 5 ] / [ (3 * 4 + 1) / 4 ]
= [ -9 / 5 ] / [ 13 / 4 ]
= [ -9 / 5 ] * [ 4 / 13 ]
= [ -9 * 4 ] / [ 5 * 13 ]
= -36/65
another way is to do it separately first: </span>-1 4/5 and 3 1/4
-1 4/5 = -(1 + 4/5)
= -(5/5 + 4/5)
= -9/5
3 1/4 = 3 + 1/4
= 3*4/4 + 1/4
= 12/4 + 1/4
= 13/4
so (-1 4/5) / ( 3 1/4)
= (-9/5) / (13/4)
= (-9/5) * (4/13)
= (-9*4) / (5*13)
= -36/65
