Checkpoint 1
Assess Your Understanding
(page 25)
1.1
1. Answers will vary.
a) Inch; I used my eraser, which is approximately 2 in. long. The distance from my elbow to
my wrist is about 5 erasers, or about 10 in.
b) Inch; I used the length of my thumb to the first knuckle, which is approximately 1 in. The
length of a cell phone is about 4 thumb lengths, or about 4 in.
c) Foot; I used the length of my slipper, which is approximately 1 ft. long. The width of the
1
bed is about 3 slippers, or about 3 ft. 6 in.
2
d) Foot; I used the height of the hockey net as a referent, which is about 3 ft. I estimated that
the gymnasium is about 6 hockey nets high, which is about 18 ft.
2. Answers will vary.
3
a) 9
in.
16
b) 4
1
in.
16
3. a) 3 ft. = 1 yd.
To convert feet to yards, divide:
80
80 ft. =
yd.
Write this improper fraction as a mixed number.
3
2
80 ft. = 26 yd.
3
80 ft. = 26 yd. 2 ft.
b) 1 mi. = 1760 yd.
So, 3 mi. = 3(1760 yd.)
3 mi. = 5280 yd.
c) First, convert yards to inches. Use the conversion: 1 yd. = 36 in.
So, 2 yd. = 2(36 in.)
2 yd. = 72 in.
Then, convert feet to inches. Use the conversion: 1 ft. = 12 in.
So, 1 ft. = 12 in.
Add. 2 yd. 1 ft. = 72 in. + 12 in.
2 yd. 1 ft. = 84 in.
4. To compare the heights, convert one measurement so the units are the same.
Convert 3 ft. 11 in. to inches.
Use the conversion: 1 ft. = 12 in.
Checkpoint 1
Copyright  2011 Pearson Canada Inc.
1
So, 3 ft. = 3(12 in.)
3 ft. = 36 in.
So, 3 ft. 11 in. = 36 in. + 11 in.
3 ft. 11 in. = 47 in.
Since 47 in. < 51 in., Sidney is shorter.
1.2
5. Answers and measurements will vary. For example:
a) 25.4 m; 27 yd. 2 ft. 4 in.
b) 143 cm; 4 ft. 8 in.
c) 77 cm; 30 in.
6. I would use calipers. I would use the unit marked on the calipers.
1.3
7. Answers will vary depending on the conversion ratios used.
a) 1 yd. = 91.44 cm, or 0.9144 m
To convert metres to yards, divide:
13
13 m =
yd.
0.9144
13 m = 14.2169… yd.
13 m 14.2 yd.
1 yd. = 3 ft.
So, 0.2 yd. = 0.2(3 ft.)
0.2 yd. = 0.6 ft.
So, to the nearest foot, 13 m = 14 yd. 1 ft.
b) 1 ft. = 12 in. and 1 in. = 2.54 cm
4 ft. = 4(12 in.)
4 ft. = 48 in.
48 in. = 48(2.54 cm)
So, 48 in. = 121.92 cm
4 ft. 122 cm
c) 2 km = 2000 m
Use the conversion: 1 yd. = 91.44 cm, or 0.9144 m
2000
So, 2000 m =
yd.
0.9144
2000 m = 2187.226… yd.
1 mi. = 1760 yd.
Subtract: 2187.226… yd. – 1760 yd. = 427.226… yd.
So, 2 km 1 mi. 427 yd.
d) 91.44 cm = 1 yd.
So, 25 000 cm =
Checkpoint 1
25 000
yd.
91.44
Copyright  2011 Pearson Canada Inc.
2
25 000 cm = 273.403… yd.
1 yd. = 3 ft.
So, 0.403… yd. = (0.403…)(3) ft.
0.403… yd. = 1.209… ft.
1 ft. = 12 in.
0.209… ft. = (0.209…)(12) in.
0.209… ft. = 2.519… in.
So, 25 000 cm = 273 yd. 1 ft. 3 in.
e) 1 in. = 2.54 cm, or 0.0254 m
So, 13 000 in. = (13 000)(0.0254 m)
13 000 in. = (13 000)(0.0254 m)
13 000 in. = 330.2 m
f) 1750 mm = 175 cm
2.54 cm = 1 in.
175
So, 175 cm =
in.
2.54
175 cm = 68.897… in.
12 in. = 1 ft.
68.897
ft.
12
68.897… in. = 5.741… ft.
0.741… ft. = 12(0.741…) in.
0.741… ft. = 0.889… ft.
So, 1750 mm 5 ft. 9 in.
So, 68.897… in. =
8. The perimeter of the table is:
P = 2(30 cm) + 2(115 cm)
P = 60 cm + 230 cm
P = 290 cm
2.54 cm = 1 in.
290
So, 290 cm =
in.
2.54
290 cm = 114.173… in.
1 ft. = 12 in.
114.173
ft.
12
114.173… in. = 9.514… ft.
114.173… in. =
0.514… ft. = 12(0.514…) in.
0.514… ft. = 6.168… in.
Checkpoint 1
Copyright  2011 Pearson Canada Inc.
3
So, 290 cm 9 ft. 6 in.
10 ft. of laminate is needed.
Checkpoint 1
Copyright  2011 Pearson Canada Inc.
4
Checkpoint 1
Copyright  2011 Pearson Canada Inc.
5