Chapter 12
A snake measures 89.4 cm. Is this more or less than 1 meter?
Less than
A basement playroom is 10.5 m long. Using the scale of 2 cm = 3 m, what is the length of the playground in a scale drawing?
7 cm
Math-o-Matic is a mathematics video game. Players try to solve equations and puzzles. The Math-O-Matic screen shows two expressions: n(4 + 4), when n=5, and 150/(n + 1), when n = 2. Which expression has the greater value?
150/(n + 1)
A recipe suggest serving 250 g of meat for each person. How many kilograms of meat should Lena buy if she is serving 6 people at dinner?
1.5 kg
6 x 250 = 1500; 1500 g = 1.5 kg
Seventy five percent of registered voters cast ballots in the election. If there were 4000 registered voters, how many voted?
3000 voted
75% x 4000 = 3000
The variables of c and d have the same value in all these equations. Find their values.
c + d = 21
c - d = 1
c x d = 110
c = 11; d = 10
What is the surface area of a rectangular box 5 in. long, 3 in. wide, and 4 in. high?
94 in2
Tapes that usually cost $8 each are on sale for 30% off. What is the price for a tape on sale?
$5.60
30% x 8 = $2.40
$8 - $2.40 = $5.60
Math-o-Matic shows this series of equations. Solve them to find the value of g.
5e = 7.5
e + f = 2
f - g = 0.2
g = 0.3
How many cubic centimeters will 7.9 grams of water fill?
7.9 cm3
Hank paid $3.50 for 2 hamburgers. How much will he pay for 8 hamburgers?
$14
Tina computed these expressions to equal 1/2. Which ones are correct?
a) 25% of 8b) n/3 when n = 1.50
c) 3 and 1/8 - n, when n = 5/8.
d) 5/n x n/10, when n = 7
B & D
An aquarium measures 3 ft long, 2.5 ft wide, and 3.5 ft high. Is the volume of the aquarium more or less than an aquarium with a volume of 1yd3?
Less than
V = 3 ft x 2.5 ft x 3.5 ft = 26.25 ft3
What percent of the letters in CALIFORNIA are vowels?
50%
The perimeter of an isosceles triangle is 18 in. The congruent sides are odd numbers between 4 and 10. What are the lengths of the three sides?
5 in. 5 in. 8 in; 7 in. 7 in. 4 in.