Answer: 10
<u>Step-by-step explanation:</u>
varies directly means: 
Step 1: solve for k ⇒ 
Step 2: plug in the given value and k to solve for the missing value: 
42(5) = 21(x)

2(5) = x
10 = x
Answer:
53 cm.
Step-by-step explanation:
Circumference = pi times diameter
We are trying to find diameter so rearrange
Circumference/pi = diameter
166.5/pi = 52.998596
Approximately 53 centimeters of lace
3,500 kilometers in one day
Answer:
5cm by 1.95cm
Step-by-step explanation:
Let the length of the rectangle be x
Let the width be y
Perimeter of a rectangle = 2x + 2y
If the initial perimeter of a rectangle is about 13.9 cm, then;
13.9 = 2x + 2y ..... 1
If when the width is double the perimeter is 17.8cm, then;
17.8 = 2x + 4y ..... 2
Subtract 1 from 2;
13.9 - 17.8 = 2y - 4y
- 3.9 = -2y
y = 3.9/2
y = 1.95 cm
Substitute y = 1.95 into 1 to get x;
From 1;
13.9 = 2x + 2y
13.9 = 2x + 2(1.95)
13.9 = 2x + 3.9
2x = 13.9-3.9
2x = 10
x = 5 cm
Hence the dimension of the smaller triangle is 5cm by 1.95cm