Math 7 Focus 2.3
Strategic Standard Build
1) Find an irrational number in between 4
and 5.
3) What value of t satisfies the equation
-4t – 6 = 14?
NS 1.4
AF 4.1*
2) Bill works in a bike shop and is paid 9%
commission on his sales? In March his
total sales was $1570. To the nearest
dollar, how much did Bill earn in
commission for March?
4) In the figure below, D is the midpoint of
CB and AD is perpendicular to CB .
What is the length of AD ?
A
See Page 2
under Student Work
C
20 cm
B
D
24 cm
NS 1.7*
MG 3.3*
Lesson Objective: You will be able to solve distance problems.
Multi-Step Problems
AF 4.2*
CST TEST PREP
We Do: Solve using the formula d = rt.
I) A train traveled at an
average speed of 65 mph
for 4 hours. What is the
total number of miles the
train traveled?
d = rt
d=?
II) A duck flew 95 miles. If the
average speed of the duck
was 19 mph, how many
hours did the duck fly?
d = rt
d = 95
r = 65
t=4
r = 19
d = 65 ● 4
95 = 19 ● t
19
19
d = 260 miles
t = 5 hours
t=?
You Do: Solve using the formula d = rt.
III) A car traveled at an
average speed of 55 mph
for 7 hours. What is the
total number of miles the
car traveled?
r = 55
d = 55 ● 7
d = 385 miles
t=7
d = 84
V) A car traveled 496 miles in 8
hours. What was the
average speed of the car?
d = rt
d = 496
d = rt
d = rt
d=?
IV) A falcon flew 84 miles. If
the average speed of the
falcon was 21 mph, how
many hours did the falcon
fly?
r = 21
84 = 21 ● t
21
21
t = 4 hours
t=?
r=?
496 = 8 ● r
8
8
r = 62 mph
t=8
Student Work
1)
4
16
5
19
22
3)
-4t – 6 = 14
+6 +6
-4t + 0 = 20
-4t = 20
-4
-4
1t = -5
25
Any square root between 16 and
25 is an irrational number that
lies between 4 and 5. These are
considered NON perfect squares.
2)
t = -5
A
4)
9
x
=
100 1570
9 • 1570 = 100 • x
14130 = 100x
100
20 cm
100
x = $141.30
x ≈ $141.00
A2 + B2 = C2
C
B
D
24 cm
A
20 cm
D 12 cm B
Lesson Notes:
A = 12
B=?
C = 20
(12) 2 + (B)2 = (20)2
144 + B2 = 400
-144
-144
2
B = 256
B2 = 256
B = 16 cm
Focus 2.3 Response Form
Strategic Standards Build: Multiple Choices
1)
2)
A)
2
B)
4
C)
9
D)
20
3)
A)
5
B)
-5
C)
-2
D)
2
A)
4 cm
A)
$2
B)
$9
B)
10 cm
C)
$141
C)
14 cm
D)
$1,431
D)
16 cm
4)
Additional Practice
5) Which of the following is an irrational
number?
7) What value of t satisfies the equation
-7t – 3 = -59?
A)
2 = irrational
A)
9
B)
4 = 2 rational
B)
-9
C)
9 = 3 rational
C)
8
D)
36 = 6 rational
D)
-8
-7t – 3 = -59
+3
+3
-7t + 0 = -56
-7t = -56
-7
-7
1t = 8
t=8
NS 1.4
6) Jackie works in a book store and is paid
12% commission on her sales? In April her
total sales was $860. To the nearest dollar,
how much did Jackie earn in commission for
April?
A)
$1
B)
$10
C)
$103
D)
$1003
12
x
=
100 860
12 • 860 = 100 • x
10320 = 100x
100
100
AF 4.1*
8) In the figure below, P is the midpoint of
ON and MP is perpendicular to ON . What is
the length of ON ?
M
15 cm
12 cm
12
O
M
x = $103.20
N
P
x ≈ $103.00
12 cm
A2 + B2 = C2
A = 12
(12)
15 cm
2
B=?
C = 15
2
+ (B) = (15)2
144 + B2 = 225
-144
-144
2
B = 81
B2 = 81
NS 1.7*
A)
P
3 cm
B)
6 cm
C)
12 cm
D)
18 cm
N
B = 9 cm
ON = 2 x PN
ON = 2 x 9 cm
ON = 18 cm
MG 3.3*