# Thread: HELP~ i dun understand!!!

1. ## HELP~ i dun understand!!!

these question i dun understand.. and i dunno how to do.. can some 1 help plz.. question.. 2,3,4,5

2. Originally Posted by xiaoz
these question i dun understand.. and i dunno how to do.. can some 1 help plz.. question.. 2,3,4,5
2a $530 \div 0.025=\frac{530}{0.025}$

multiply top and bottom by $1000$:

$530 \div 0.025=\frac{1000\times 530}{1000\times 0.025}=\frac{530000}{25}$

2b The cost of dinner is the price of the food plus a 4% service charge.

A diner paid \$93.60, what was the price of the food?

Let $\x$ be the price of the food, then the diner pays:

$x+0.04x=1.04x=93.5$,

so:

$x=\frac{93.5}{1.04}$ dollars.

RonL

3. 3a.
The next number of the sequence is found by adding the previous ones. This is called fibonacci sequence.

4. 6a,
$5<6x-13<7$
$18<6x<20$
Divide by six,
$3

6b,
You have,
$\frac{7}{11}
For example if,
$x=\frac{7.5}{11}$
But express it as a fraction,
$x=\frac{\frac{15}{2}}{11}=\frac{15}{22}$

6c,
You have,
$x^{2y}=5$
then cube both sides,
$x^{6y}=125$
Mutiply by 2,
$2x^{6y}=250$
subtract by four,
$2x^{6y}-4=246$