Answer:
The value of the test statistic is -2.64.
Step-by-step explanation:
The test statistic is:

In which X is the sample mean,
is the expected(claimed) mean,
is the standard deviation and n is the size of the sample.
An automobile manufacturer claims that its van has a 40.3 miles/gallon (MPG) rating.
This means that 
After testing 250 vans, they found a mean MPG of 39.9. Assume the standard deviation is known to be 2.4.
This means, respectively, that:

So



The value of the test statistic is -2.64.
Answer:
8 one-dollar bills
3 five-dollar bills
2 ten-dollar bills
Step-by-step explanation:
Let x = # of one-dollar bills, y = # of five-dollar bills, and z = # of ten-dollar bills. Total amount in the wallet is $43, so the first equation would be 1x + 5y + 10z = 43. Next, there are 4 times as many one-dollar bills as ten-dollar bills, so x = 4z. There are 13 bills in total, so x + y + z = 13
x + 5y + 10z = 43
x = 4z
x + y + z = 13
x + 5y + 10z = 43
x + 0y - 4z = 0
x + y + z = 13
5y + 14z = 43
-y - 5z = -13
5y + 14z = 43
-5y - 25z = -65
-11z = -22
z = 2
x = 4z
x = 4*2 = 8
x + y + z = 13
8 + y + 2 = 13
10 + y = 13
y = 3
Answer:
Did you know Grapes light on fire in the microwave..
Step-by-step explanation:
Answer:
1. 35 - 176 = -141
2. 0.55 × 1.79 = 0.9845
3. 11.38 × 5.46 = 62.1348
Hope it helps and have a great day! =D
~sunshine~
Answer:
1.98 × 10^10
Step-by-step explanation:
First solve for how many text messages were sent out per one month:
22,000,000 × 900
19,800,000,000
Convert into scientific notation:
1.98 × 10^10
In scientific notation, there can only be one number before the decimal. The rest of the numbers must be after the decimal; hence, why I put the numbers 9 and 8 after the decimal. If the rest of the numbers are zeros, you do not have to add them after the decimal. Instead, starting from right to left, count the number places until you reach your decimal. The number you have counted will be your exponent. I counted nine 0's, one 8, and one 9 which made this exponent 10 as there were 10 decimal placements.