1) \((-7)(6)=\color{red}{-42}\)
Solution
One factor is negative, so the result is negative.
Multiply absolute values: \(7\times6=42\), so \(-42\).
2) \((-8)(-5)=\color{red}{40}\)
Solution
Two negatives make a positive.
\(8\times5=40\).
3) \(45\div(-9)=\color{red}{-5}\)
Solution
Different signs give a negative quotient.
\(45\div9=5\), so \(-5\).
4) \((-56)\div(-7)=\color{red}{8}\)
Solution
Same signs give a positive quotient.
\(56\div7=8\).
5) \(12(-4)(-3)=\color{red}{144}\)
Solution
Two negative factors give a positive product.
\(12\times4\times3=144\).
6) \((-9)(-2)(-5)=\color{red}{-90}\)
Solution
Three negative factors give a negative product.
\(9\times2\times5=90\), so \(-90\).
7) \((-84)\div 12=\color{red}{-7}\)
Solution
Different signs give a negative quotient.
\(84\div12=7\), so \(-7\).
8) \(96\div(-16)=\color{red}{-6}\)
Solution
Different signs give a negative quotient.
\(96\div16=6\), so \(-6\).
9) \((-11)(13)=\color{red}{-143}\)
Solution
One negative factor gives a negative product.
\(11\times13=143\), so \(-143\).
10) \((-144)\div(-18)=\color{red}{8}\)
Solution
Same signs give a positive quotient.
\(144\div18=8\).
11) \(5(-6)(-2)(-3)=\color{red}{-180}\)
Solution
There are three negative factors, so the product is negative.
\(5\times6\times2\times3=180\), so \(-180\).
12) \((-120)\div 5\div(-4)=\color{red}{6}\)
Solution
Work left to right: \((-120)\div5=-24\).
Then \((-24)\div(-4)=6\).
13) \((-15)(-4)\div(-6)=\color{red}{-10}\)
Solution
First \((-15)(-4)=60\).
Then \(60\div(-6)=-10\).
14) \(18\div(-3)\times(-7)=\color{red}{42}\)
Solution
Work left to right: \(18\div(-3)=-6\).
Then \((-6)(-7)=42\).
15) \((-2)(-3)(-4)(-5)=\color{red}{120}\)
Solution
Four negative factors give a positive product.
\(2\times3\times4\times5=120\).
16) \(240\div(-8)\div 3=\color{red}{-10}\)
Solution
Work left to right: \(240\div(-8)=-30\).
Then \((-30)\div3=-10\).
17) \((-36)(5)\div(-9)=\color{red}{20}\)
Solution
First \((-36)(5)=-180\).
Then \((-180)\div(-9)=20\).
18) \((-7)(8)(-2)\div(-4)=\color{red}{-28}\)
Solution
First \((-7)(8)=-56\).
Then \((-56)(-2)=112\).
Finally \(112\div(-4)=-28\).
19) \(420\div(-6)\times(-3)\div 7=\color{red}{30}\)
Solution
Work left to right: \(420\div(-6)=-70\).
Then \((-70)(-3)=210\), and \(210\div7=30\).
20) \((-9)(-5)(-4)\div(-10)\times 2=\color{red}{36}\)
Solution
First \((-9)(-5)=45\).
Then \(45(-4)=-180\), \((-180)\div(-10)=18\), and \(18\times2=36\).