Answer:
Step-by-step explanation:
Median = middle number
Total ten numbers so
median = (17 + b)/2
given median = 18
so
(17 + b)/ 2 = 18
17+b = 36
b = 36 - 17
b = 19
Now you have the data set
7, a , 12, 15 , 17, 19, 20, 22, 24 , 25
Mean = (7 + a + 12+ 15 +17 + 19 + 20 + 22 +24 +25)/ 10
Given mean = 17
so
17 = (7 + a + 12+ 15 +17 + 19 + 20 + 22 +24 +25)/ 10
17 = (a + 161) / 10
a + 161 = 170
a = 170 - 161
a = 9
answer
a = 9
b = 19
Packet of 12 pencils = p
Packet of 30 rulers = r
p = £2.15
r = £6.00
£35 = 4r + xp
£35 = 4(£6.00) + x(£2.15)
£35 = £24 + £2.15x
£11 = £2.15x
x = 5.12
Since she can buy 5.12 packets of pencils, it is equal to 5 packets of pencils.
Answer:
2 Hours
Step-by-step explanation:
Required man hours to complete the full job = 12 *15
=180 Man hours
Required man hours to complete the 2/5 of the job = 180/5
= 36 Man hours
if 18 peoples are working,
required hours to complete the 2/5 of the job = 36 /18
= 2 hours
