Math problems, can anybody help?

Question

-12+1/4=?

Element / Melting point (C) / Boiling point (C)
Radon / -71 /-61.8
Neon /-248.7 / -246
Bromine /-7.2 /58.8

a. for each of these elements, find the differnce between its boiling point and melting points.

b. which of the elements is liquid in the widest range of temperatures?

c. which of the elements is lquid at 0 C



Explain whether it is always true that the differnce between two numbers is smaller than either of the numbers? Give an example to justify your answer.

Please help, they are part of my math homework and I do not understand what it is talking about and I was hoping that one of you guys would know. Please I need some answers ASAP.
!!!

Answer 1

-12 + 1/4 = -11 4/4 + 1/4 = -11 3/4

a. Radon: -61.8 - (-71) = -61.8 + (+71) = 71 - 61.8 = 9.2
9.2 degrees C

See if you are able to solve the other 2 yourself. Hint: Minus a negative is the same as plus a positive.

Neon: -246 - (-248.7) = ?

Bromine: 58.8 - (-7.2 ) = ?

b. Bromine. Figure out why from looking at your work in a.

c. Bromine because although all have melting points under 0 C, the others are vapors at 0 C.

It is not always true. 7-(-1)=8. The difference is 8 and it is not smaller than 7, nor is it smaller than -1.

Answer 2

slow down, read the problem carefully, think about what it is saying and asking

a. the difference in the boiling and melting points is found by just subtracting the melting poing from the boiling point

for Radon that would be -61.8-(-71)=9.2

do the others the same way

b. which element has the widest range? that just mean which answer from a is the biggest number (in other words, something is only liquid if the temperature is above its melting and below its boiling, water is liquid only above 0 C and below 100 C and therefore has a range of 100 between the two)

c. which is liquid at 0? which one has 0 in between the melting and boiling point
notice that two of them boil below zero, so they can't be liquid at zero, only one has a boiling point higher than zero


and as for that explanation, clearly it is not true that the difference between two numbers is always smaller than either number

here's two numbers 2 and 8
the difference between them is 6

6 is not smaller than 2, so the difference between two numbers is NOT always smaller than either number

good luck

Answer 3

-12 + 1/4 = - 11 3/4
we can put a rule for the signs when we add
suppose a , b is 2 +ve real numbers ....a >b
a + b = | a + b |
a - b = | a - b |.
b - a = - |a - b|
in simple words ..when we have 2 different signs we take the sign of the great number and then we subtract

a) difference between boiling and melting point for
Rn = - 61.8 - ( - 71) = 8.2 °c
Ne = - 246 - (-248.7) = 2.7°c
Br = 58.8 - (-7.2) = 66°c


b) Bromine


c) Bromine

Answer 4

-12 + 1/4 = -11¾

a) Radon 9.2
Neon 2.7
Bromine 66

b) Bromine

c) Bromine

the difference between two numbers can be larger than either of the two numbers. Conside the differenc between 2 and -2, which is 4

Answer 5

-12+1/4 =-11and 3/4ths
a. boiling point minus melting point
b. answer, greatest numbaer from a.
c. Bromine, only one where 0 is within the range of numbers

no the difference between two numbers does not have to be smaller thatn the two number, ex. 2-(-1)=3

Answer 6

all i know is 2+2=5.

Answer 7

11.75
radon 9.2
neon 2.7
Bromine 66










bromine










Bromine










5-{-2}=7