SES 4th Unknowns

Unknowns Addition

100

4 + 5 = a

a = 9

200

7 + 7 = x

x = 14

300

4 + x = 12

x=8

400

z + 42 = 57

z = 15

500

49 + ? = 74

?= 25

Unknowns Subtraction 1

100

97 - 3 = a

a = 94

200

87 - 4 = c

c = 83

300

a - 15 = 20

a = 35

400

42 - t = 37

t = 5

500

z - 43 = 72

z = 115

Unknowns Subtraction 2

100

8 - h = 4

h = 4

200

15 - x = 13

x = 2

300

47 - r = 13

r = 34

400

52 = 64 - n

n = 12

500

44 = 85 - x

x = 41

Mystery Equation

100

3 + p = 8

p = 5

200

k - 10 = 12

k = 22

300

124 - q = 

q = 56

400

56 + m = 68

m = 12

500

685 - p = 507

p = 178

Vocabulary

100

The letter which takes the place of an unknown number in an equation is called a ____________.

What is a variable

200

True or False?

The math operation that uses the words "less than", "how many more", "take away", and "minus" is called, Addition.  

False-What is Subtraction

300

True or False?

The first step in solving an equation with a variable is to find the math operation.

True

400

True or False?

When solving a subtraction problem and the first number is the variable (ex:  m - 10 = 2), you must add the other numbers together to find the variable.

True

500

True or False:

When solving a subtraction problem with a variable in the second position of an equation (ex:  26 - n = 22), you must add the other known numbers together to get the answer.

False:  You would put the larger number on top, and subtract the smaller number on the bottom:  

        26

   -    22

  n =  4