Answer:
4000
Step-by-step explanation:
The 2 angles at a vertex are supplementary (one interior and one exterior) the exterior angle is = the the sum of the 2 remote interior angles..
The average of 4, 9, 16, 25 and x is 2x means that;
(4+9+16+25+x)/5=2x
Multiply both side by 5
5(54+x)/5=2x(5)
54+x=10x
Subtract x to both side
54+x-x=10x-x
54=9x
Divided 9 to both side
54/9=9x/9
x=6
Check:
Substitute x with 6
(4+9+16+25+x)/5=2x
(4+9+16+25+6)/5=2(6)
60/5=12
12=12; so x=6 which marks B as the correct answer. Have a nice day!
Step 1 should have been 27(6+30).
Answer:
They are both correct
Step-by-step explanation:
It's interpretation of the concept. In common practice multiplying by 10 means you add a zero and that's what we teach 10 year olds. But what does adding a zero mean? It means adding a place value and that's what you learn when you are
So in both examples just add a decimal:
2.0 x 10 = 20.
0.2 x 10 = 2.0
In conclusion, it depends on the level of precision required in the discussion and the level of maturity as to who is correct in their examples. If you are teaching 3rd graders math, by all means you add a zero. If you are discussing physics you are shifting over a place value.
