Answer:
Step-by-step explanation:
5/y + 7/x =24.........(1)
12/y + 2/x =24........(2)
Let 1/y = a and 1/x = b
5a + 7b = 24 ...........(3)
12a + 2b = 24...........(4)
Multiply (3) by 2 and (4) by 7
10a + 14b = 48..........(5)
84a + 14b = 168.........(6)
Substracting (5) from (6)
84a - 10a = 168 - 48
74a = 120
a = 120/74
a = 60/37
Putting a = 60/37 in (3)
5a + 7b = 24
5(60/37) + 7b = 24
300/37 + 7b = 24
Multiply each term 37
300 + 259b = 888
259b = 888 - 300
259b = 588
b = 588/259
And a = 1/y
60/37 = 1/y
Cross multiply
60y = 37
y = 37/60
Also
b = 1/x
588/259 = 1/x
Cross multiply
588x = 259
x = 259/588
6(c-20)≤360 divide both sides by 6
c-20≤60 add 20 to both sides...
c≤80
So the original cost of chairs must be $80.00 or less.
Answer:
A x>9
Step-by-step explanation:
add 4 to both sides and ta da
Ok: the question is basically asking what is the percentage of the black marbles he had pulled with replacements. You look at the graph and count how many black marbles he pulled,6, and then find the total of marbles he pulled after the experiment ,20. So, you take (6/20) which then gives you an answer of .3 which is a 30%.
Answer:
¬(W∨S)→¬(J∨E)
D→(B∨C)
X is true
No
Step-by-step explanation:
The hypotheses "neither water nor soft drinks can quench your thirst" translates to ¬(W∨S) ("neither nor" negates the disjunction W∨S). The "if,... then" translates to the implication symbol (arrow). The conclusion "juice will not do it, unless the juice contains electrolytes" translates to ¬(J∨E). This is because if J or E were true, then J would be true (because E implies J), contrary to the conclusion that J is false ("juice will not do it"), then J∨S is false.
The hypothesis here is "the dyer breaks" hence D is the hypothesis. The conclusion is "we will hang the clothes to dry, or take the clothes to a coin-operated laundry" which is the same as (B∨C).
The proposition p→p is always true (according to truth tables). In this case, p:=X is true, then p is true and X is true.
X∨Y is false if and only if X is false and Y is false, so both statements X,Y must be false.