Ratios

Shipment Number of Defective Chips in the Shipment Total number of Chips in the Shipment S1 2 5,000 S2 5 12,000 S3 6 18,000 S4 4 16,000 A computer chip manufacturer expects the ratio of the number of defective chips to the total number of chips in all the future shipments to equal the corresponding ...

Coordinate Geometry

In the rectangular coordinate system, are the points (r,s) and (u,v) equidistant from the origin?

1) r+s = 1

2) u=1-r and v= 1-x

I could not understand the logic behind

Step 3: Determine the ratio in the mixture.
The ratio of M to D in the mixture is the RECIPROCAL of the distances in red.
M : D = 15000:5000 = 3:1.

Where did we derive that the ratio has to be reciprocal. Why is this the case?? :!: :

Percents

Are at least 10% of the people in country X who are 65 years old or older employed?

1) In country X, 11.3 percent of the population is 65 years old or older.

2) In country X, of the population 65 years old or older, 20 percent of the men and 10 percent of the women are employed.

Mixtures

A contractor combined x tons of a gravel mixture that contained 10% gravel G, by weight, with y tons of a mixture that contained 2 percent of the gravel G, by weight, to produce z tons of a mixture that was 5 percent gravel G, by weight. What is the value of x? 1) y = 10 2) z = 16 I need some genera...

Arthematic Sequence

When a certain tree was first planted, it was 4 feet tall, and the height of the tree increased by a constant amount each year for the next 6 years. At the end of 6th year, the tree was 1/5 taller than it was at the end of 4th year. By how many feet the height of the tree increase each year? 1) 3/10...

Number Properties

If ax + b = 0, is x>0

(a) a + b > 0

(b) a - b > 0