MIXED APPLICATIONS 21. In 1960, the average speed of passenger
aircraft within the U. S. was 235 miles per
hour. By 1978 the average speed was 1.74
times that amount. To the nearest whole
number, what was the average speed in 1978?
Help mepleaee

Average speed of passenger aircraft in 1978 is 408.9 mph

Step-by-step explanation:

Here, in the question, we are tasked with giving the value of the average speed of the passenger aircraft in the US for the year 1978, given that it is a certain multiple of the value in 1960.

So what we will be doing here is to get the value of the average speed and it can be gotten by multiplying the average speed in 1960 by the multiple to which the speed is, now in 1978.

From the question, we can write a formula for this;

Average speed of passenger aircraft in 1978 = 1.74 * average speed of passenger aircraft in 1960

From the question, we have that the average speed of passenger aircraft in 1960 = 235 mph

Thus,

Average speed of passenger aircraft in 1978 = 1.74 * 235 = 408.9 mph

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1

34

step-by-step explanation: