สัญกรณ์นะจ่ะ

5×5×5

• 110

• 115

• 120

• 125

x(t) is a _______________ signal if

x(t) = 0, t < 0

A signal y(t) can only be described in terms of mean value or mean square value. This signal is said to be a ______________ signal.

Eric bought 2 bags of potatoes. There were 78 potatoes in each bag. How many potatoes did Eric buy?

What operation are you doing?

• multiplication

• division

• subtraction

• addition

• Addition

• Subtraction

• Multiplication

• Division

Multiply

• 5 / 18
• 16 / 15
• 28 / 9
• 4 / 9

Reduce:  6/15

• 2/5
• 3/5
• 4/9

Multiply

• 6
• 4 / 45
• 20
• 7 /45

• Addition

• Subtraction

• Multiplication

• Division

A city bought 2 pieces of land to build a new highway. Each piece of land cost the city $274,390. How much did the city spend on the land?

What operation are you doing?

• multiplication

• division

• subtraction

• addition