Step-by-step explanation:
it's ur answers I hope it's helpful..
10 students averaged 80, so the sum of their scores was (10 x 80) = 800
20 students averaged 89, so the sum of their scores was (20 x 89) = 1,780
All together, the sum of all 30 scores was (800 + 1,780) = 2,580
30 students totaled 2,580, so their average was (2,580 / 30) = <em> 86</em> .
Answer:
DE = 18
Step-by-step explanation:
Given that,
Point D is on line segment CE.
DE = x+10, CD=6 and CE=3x
We need to find the length of DE.
ATQ,
CE = CD + DE
Putting all the values,
3x = 6 + x+10
Taking like terms together
3x-x = 16
2x = 16
x = 8
DE = x+10
= 8+10
= 18
Hence, the length of DE is 18.