Question

name:
unit 2 review
1 list the first 10 multiples of 4
2 list all the factors of 20:
3 draw all the arrays that show 12

1. find the area and perimeter of the rectangle.

9 feet
2 feet
area
perimeter:

1. fill in the rest of the pattern.

2, , 12, , 22, , 32

Explanation:

Step1: Find the first 10 multiples of 4

Multiply 4 by 1, 2, 3, ..., 10.
$4\times1 = 4$, $4\times2=8$, $4\times3 = 12$, $4\times4=16$, $4\times5 = 20$, $4\times6=24$, $4\times7 = 28$, $4\times8=32$, $4\times9 = 36$, $4\times10=40$

Step2: List all the factors of 20

Find pairs of numbers that multiply to 20.
$1\times20 = 20$, $2\times10=20$, $4\times5 = 20$. So the factors are 1, 2, 4, 5, 10, 20

Step3: Draw arrays for 12

Arrays are rectangles. Find pairs of numbers that multiply to 12.
$1\times12$ (1 row of 12), $2\times6$ (2 rows of 6), $3\times4$ (3 rows of 4)

Step4: Calculate area and perimeter of the rectangle

Area formula: $A = l\times w$. Perimeter formula: $P=2(l + w)$
$A=9\times2=18$ square feet. $P = 2(9 + 2)=2\times11 = 22$ feet

Step5: Fill in the pattern

The pattern increases by 5 each time.
$2+5 = 7$, $12+5=17$, $22+5 = 27$

Answer:

1. 4, 8, 12, 16, 20, 24, 28, 32, 36, 40
2. 1, 2, 4, 5, 10, 20
3. Arrays: 1×12, 2×6, 3×4 (draw rectangles accordingly)
4. Area: 18 square feet; Perimeter: 22 feet
5. 7, 17, 27