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Line A is parallel to the line 4y+12x=24. Find the equation of Line A if it passes through the point (5,40/3).

Line A and line 4y+12x+24 are parallel. This means that they have the same gradient. In y=mx+c the gradient of the line is m. We can rearrange the equation 4y+12x+24 to find m. To begin with subtract 12x fro...
CB
Answered by Chloe B. • Maths tutor
3569 Views

C and D are two events such that P(C) = 0.2, P(D) = 0.6 and P(C|D) = 0.3. Find P(D|C), P(C’ ∩ D’) & P(C’ ∩ D)

Here we use the formula for conditional probability:P(C|D)xP(D)=(𝑃(C∩D))= 0.3x0.6=0.18Note: 𝑃(C∩D)=𝑃(D∩C)=0.18Hence P(D|C)=𝑃(D∩C)/P(C) = 0.18/0.2 = 0.9P(C'∩D') = P(C'|D')xP(D')P(C'|D) = 0.7P(D')=0.4P(C')=0.8...
SV
Answered by Sunny V. • Maths tutor
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Solve the simultaneous equations 3x + 2y = -7 and x=4y+21

Substitute in the second equation into the first to eliminate x from the first equation. Solve for y which should, when solved (shown below), equal -5. Sub -5 back into either equation in the place of y to t...
JG
Answered by Jamie G. • Maths tutor
4010 Views

Matt has 3 piles of coins, A , B and C. Altogether there was 72p. Pile B had twice as much as pile A. Pile C had three times as much as pile B. How much money was in Pile C?

so we know that A+B+C= 72. We also know that B=2A (1) and C=3B which means C=6A (2) and with this information we can re arrange to equation to be only have one variable. so A+2A+6A= 72 Collecting all the ter...
ND
Answered by Nazli D. • Maths tutor
4146 Views

The new reading for James' electricity bill is 7580, and the old reading is 7510, the price per unit is 13p, how much does James have to pay for his electricity?

This question is tricky/unfair because you need to understand how meters work. The old reading was the last time the electricity bill was paid for, so the first thing you need to do is 7580-7510= 70. So that...
MZ
Answered by Michal Z. • Maths tutor
3400 Views