Step-by-step explanation:
the circumference of a circle is
C = 2×pi×r
with r being the radius.
the square side length is 22 cm. so, the circumference or perimeter of the square (and therefore the length of the wire) is
4×22 = 88 cm.
now, it is the same wire of the same length that is now forming a circle.
so, the circumference of the square is also the circumference of the circle.
therefore,
88 = 2×pi×r
44 = pi×r
r = 44/pi = 14.00563499... cm
so, rounded, radius = 14 cm.
Answer:
Confidence interval: (0.04649,0.04913)
Step-by-step explanation:
We are given the following in the question:
Sample size, n = 100,000
Number of people who donated, x = 4781
95% Confidence interval:
Putting the values, we get:
is the required 95% confidence interval for the true proportion of their entire mailing list who may donate.
Answer:
3 + 4 = 7 which is true.
Step-by-step explanation:
Whenever you have an equation with a plain variable (that is, no exponent included), there is only one number that will work when substituted for x.
To solve it, you have to "undo" what is done to the variable. You also go in the reverse order of operations, so you do the addition/subtract first, then multiplication/division.
You also have to do the same to both sides, kind of like keeping a balance scale in balance.
In this case, we subtract 4 from both sides first:
3x + 4 -4 = 7 - 4
The + 4 - 4 cancel each other out, so you get:
3x = 3
3x means "3 times x" so you divide by 3 to undo it. I will use the / to indicate division:
3x / 3 = 3 /3
so 1x = 1.
Since 1x is "1 times x" it is the same as x by itself, so:
x=1
AND, if we substitute 1 back into the original equation (the asterisk stands for multiply):
3 * 1 + 4 = 7
3 * 1 is 3, so:
3 + 4 = 7 which is true.
1 is the only number that works.
Hope this helped.