Transcript Mental Math Strings

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Start with today’s date
(1/19/2011) (day only)
Add the digits
Multiply by the day of the month
of tomorrow
Multiply by ½
Take the square root
Add ‘3 squared’
Start with today’s date
(1/19/2011) (day only)
Add the digits
Multiply by the day of
the month of tomorrow
Multiply by ½
Take the square root
Add ‘3 squared’
19
1+9 =
10
10 * 20 =
200
200*1/2 =
100
100
10
10+32 = 10+9 =
19
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Start with the number of sides in a
pentagon
Add the number of sides in a triangle
Divide by the number of sides in a rhombus
Multiply by the number of diagonals in a
rectangle
Add the number of linear sides of a circle
Add the square of the number of sides in a
parallelogram
Divide by the square root of the number of
sides in a trapezoid
Start with the number of
sides in a pentagon
Add the number of sides in
a triangle
Divide by the number of
sides in a rhombus
Multiply by the number of
diagonals in a rectangle
Add the number of sides in
a circle
Add the square of the
number of sides in a
parallelogram
Divide by the square root
of the number of sides in a
trapezoid
5
5+3 =
8
8/4 =
2
2*2 =
4
4+0 =
4
4+42 = 4+16 =
20
20
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10
Start with the year the US declared its
independence
2. Add the digits
3. Multiply by 10
4. Add three decades
5. Divide by 8
6. Add the number of eggs in a dozen
7. Divide by number of eggs in half a
dozen
8. Square that number
1.
Start with the year the US
declared its independence
Add the digits
Multiply by 10
Add three decades
Divide by 8
Add the number of eggs in a
dozen
Divide by number of eggs in
half a dozen
Square that number
1776
1+7+7+6 =
21
21*10 =
210
210 +3(10) =
240
240/8 =
30
30+12 =
42
42/6 =
7
72 =
49
Consider y = 6x + 12.
2. Write down the y-intercept.
3. Add the slope of the line.
4. Divide that by the x-intercept.
5. Add the value of y when x = ½ .
6. Add the value of x when y is 6.
7. Multiply that by the square of the zero of
the function.
1.
Consider y = 6x + 12
Write down the y-intercept.
12
Add the slope of the line.
18
Divide that by the x-intercept.
-9
Add the value of y when x = ½ .
6
Add the value of x when y is 6.
5
Multiply that by the square of the
zero of the function.
20
Write down the tan 45° .
2. Divide that by the sin 30° .
3. Cube this value.
4. Multiply that result by cos 120° .
5. Add the sin 270° .
6. Multiply by cos 180° .
7. Multiply by 5π/4 .
8. Call your answer x and write down the
tan(x).
1.
Write down the tan 45° .
1
Divide that by the sin 30° .
2
Cube this value.
8
Multiply that result by cos 120° .
-4
Add the sin 270° .
-5
Multiply by cos 180° .
5
Multiply by 5π/4 .
Call your answer x and write down
the tan(x).
25π/4
1