JSS 1 Mathematics Flashcards: Open Sentences, Symbols and Missing Values

Question 1

What is an open sentence in mathematics?

Accepted Answer

A statement containing an unknown whose value can make it true or false.

Question 2

Find the value of $x$ in $x+7=19$.

Accepted Answer

12

Question 3

Find $n$ if $n-9=14$.

Accepted Answer

23

Question 4

Find $p$ if $6p=42$.

Accepted Answer

7

Question 5

Find $q$ if $q/5=8$.

Accepted Answer

40

Question 6

What number makes $17+\square=30$ true?

Accepted Answer

13

Question 7

What number makes $45-\triangle=18$ true?

Accepted Answer

27

Question 8

Which value makes $3x+1=16$ true?

Accepted Answer

5

Question 9

If $a=4$, what is the truth value of $a+5=10$?

Accepted Answer

false

Question 10

Which equation shows that addition and subtraction are inverse operations?

Accepted Answer

If $x+8=15$, then $x=15-8$.

Question 11

Which equation shows that multiplication and division are inverse operations?

Accepted Answer

If $7x=35$, then $x=35/7$.

Question 12

What value of $m$ makes $2m=18$ true?

Accepted Answer

9

Question 13

What value of $y$ makes $25-y=11$ true?

Accepted Answer

14

Question 14

If ★ represents a number and ★ + 6 = 21, what does ★ represent?

Accepted Answer

15

Question 15

Replace the box with a letter in the open sentence $4+\square=13$.

Accepted Answer

$4+x=13$

Question 16

Which value does NOT satisfy $x<5$: 1, 3, 4 or 6?

Accepted Answer

6

Question 17

What number makes both $x+2=9$ and $2x=14$ true?

Accepted Answer

7

Question 18

If $b/4=6$, which substitution verifies the solution?

Accepted Answer

$24/4=6$

Question 19

Why should a solution be substituted back into an open sentence?

Accepted Answer

To verify that it makes the sentence true.

Question 20

The sentence $8+5=13$ is closed rather than open because ____.

Accepted Answer

it contains no unknown value

Strong work.