a cell phone battery uses 1/3 of its charge in 3/8 of a day. How much charge will it use in one day?

1 answer:

3 0

$\bf \begin{array}{ccll}charge&day\\\cline{1-2}\frac{1}{3}&\frac{3}{8}\\\\x&1\end{array}\implies \cfrac{~~\frac{1}{3}~~}{x}=\cfrac{~~\frac{3}{8}~~}{1}\implies \cfrac{~~\frac{1}{3}~~}{\frac{x}{1}}=\cfrac{3}{8}\implies \cfrac{1}{3}\cdot \cfrac{1}{x}=\cfrac{3}{8}\\\\\\\cfrac{1}{3x}=\cfrac{3}{8}\implies 8=9x\implies \cfrac{8}{9}=x$

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Carlo puts tins into small boxes and into large boxes. He puts 6 tins into each small box. He puts 20 tins into each large box.

meriva

Answer: Carlo is incorrect

Step-by-step explanation:

3000/(2+3) = 600 (each ratio)

2:3 = 2(600):3(600) = 1200:1800

1200/6 = 200 small boxes

1800/20 = 90 large boxes

290 boxes altogether (large and small)

(large boxes/boxes altogether)x100

(90/290)x100 = 31%

31%>30%

Therefore Carlo is incorrect

8 0

2 years ago

8. Mohan wants to buy a trapezium shaped field.

mojhsa [17]

Answer:

The length of the side along the river is 140 m

Step-by-step explanation:

Equations

To solve the problem, we need to recall the area of a trapezium is:

$\displaystyle A=\frac{b1+b2}{2}.h$

Where b1 and b2 are the lengths of the parallel sides and h is the height of the trapezium.

The field to be bought by Mohan has a trapezium shape with a side along the road of side x and a side along the river of side 2x, as stated in the problem.

Knowing the height is h=100 m, and the area is 10500 m2:

$\displaystyle \frac{x+2x}{2}\cdot 100=10500$