Answer:
a)ab=10cm,r=10cmhgggkoifytewubbbcgkjjgyuuresgbvcguytrewsdyoohfutrfhje
Let 
be the 20 marks of the boys, and 
be the 10 marks of the girls.
We know that the global mean was 70, meaning that
Multiplying both sides by 30 we deduce that the sum of the scores of the whole classroom is
By the same logic, we work with the marks of the boys alone: we know the average:
And we deduce the sum of the marks for the boys:
Which implies that the sum of the marks of the girls is 
And finally, the mean for the girls alone is
The answer to your question is true
Answer:
26
Step-by-step explanation:
56cm-48cm=8cm
18cm+8cm=26cm
Answer:
<h3>
44</h3>
Step-by-step explanation:
z - some integer
2z - first given even integer (the smaller one)
2z+2 - even integer consecutive to 2z (the larger one)
2(2z) - twice the smaller number
2(2z) - 40 - the number 40 less than twice the smaller number
2(2z) - 40 = 2z + 2
4z - 40 = 2z + 2
2z = 42
2z+2 = 42+2 = 44
check:
2(2z)-40 = 2(42)-40 = 84-40 = 44
