Can any kind soul help me ASAP!
1 answer:
Answer:
Hope it helps u
Step-by-step explanation:
As we know that ,
Mean = sum of the terms/ numbers of terms
But here grouped data is given so , we use the formula
Mean=∑[f. m]/ ∑f
where f is frequency and m is mid point of each height ,
Now first we have to find the mid point of each interval, where
midpoint of each interval = (lower boundary + upper boundary)/2
m1=(150+154)/2 = 152
m2=(155+159)/2= 157,now found other by same formula, for each interval
m3= 162
m4= 167
m5=172 Now we find the midpoint of each interval ,so now
∑[f. m]=f1*m1+f2*m2+f3*m3+f4*m4+f5*m5
now putting the values of each frequency for given interval and midpoint of each interval we will get,
∑[f. m]=456+942+1296+167*x+344 = 167*x+3038
Now find,
∑f=f1+f2+f3+f4+f5
∑f=19+x
Now we have,
∑[f. m]=167*x+3038
∑f=19+x
also given mean height=161.6 cm
putt these values in above equation we get,
161.6=
now solve this ,
161.6(19+x)=167*x+3038
3070.4+161.6*x=167*x+3038
3070.4-3038=167*x-161.6*x
32.4=5.4*x
x=32.4/5.4
<h2>x=6 Ans........</h2>You might be interested in
Answer:
3.189 seconds
Step-by-step explanation:
You want f(t) = 0, so ...
0 = -16t^2 +13.4t +120
0 = t^2 -0.8375t -7.5 . . . . divide by -16
0 = (t^2 -0.8375t +0.41875^2) -7.5 -0.41875^2 . . . . complete the square*
0 = (t -0.41875)^2 -7.6753515625 . . . . write as a square
√7.6753515625 = t -0.41875 . . . . . . . . add 7.67... and take positive root
t = 0.41875 +√7.6753515625 ≈ 3.189192 . . . . add 0.41875
It will take the rock about 3.189 seconds to hit the ground.
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* We complete the square by adding the square of half the coefficient of the linear term (= (-0.8375/2)^2) inside parentheses and subtracting the same amount outside parentheses. This gives a form inside parentheses that is ...
(t^2 -2at +a^2) = (t -a)^2
Completing the square is complicated a little bit by a leading coefficient that is not 1. That is why we divided by -16 first.
_____
<em>Comment on the question</em>
We note that the rock "falls" from the 120 foot high balcony by first traveling upward at a rate of 13.4 feet per second. We also note that the height function is written f(x), but uses t as the variable. That is, it should be f(t) = ...
