Answer:
6
Step-by-step explanation:
3(1)=3 3(2)=6 3(3)=9 3(4)=12 3(5)=15
3(6)=18 3(7)=21 3(8)=24
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3(6)=18 is closest to 20
so the greatest number of batches Xiaoming can make is 6.
Answer:
Step-by-step explanation:
-7x + 12 + (-8x + 48) = 180
-15x + 60 = 180
-15x = 120
x = -8
m<BDC= -7(-8)+ 12 = 56 + 12 = 68
m<CBA = -8(-8)+48 = 64+48 = 112
Answer:
-2
Step-by-step explanation:
2(x-3), x=2
Since we know what x equals, plug it into the equation
2(2-3)
2(-1)
-2
Step-by-step explanation:
your teacher was very nice and warned you about the trap in the question.
so, really, what do we have to do ?
a full circle represents 360°.
the shaded sector is the full circle minus the white sector !
this is the same as directly calculating the shaded sector for 360-75 = 285°.
so, the area of a circle is
pi×r²
in our case
pi×20² = 400pi
the needed fraction of the whole circle is either
75/360, if we want to subtract it for the solution
or
285/360, if we want to calculate the solution directly.
both lead to the same result.
400pi×360/360 - 400pi×75/360 =
= 400pi × 285/360 = 10pi × 285/9 = 2850pi/9 =
= 316.6666666...pi ≈ 316.7pi