<h2>Answer:</h2>
Number of biology textbooks sold: 257 textbooks
Number of psychology textbooks sold: 181 textbooks
<h2>Explanations:</h2>
Let the total number of biology textbook sold be "a"
Let the total number of psychology textbook sold be "b"
If a textbook store sold a combined total of 438 biology and psychology textbooks in a week, then:
a + b = 438 ................... 1
If the number of psychology textbooks sold was 76 less than the number of biology textbooks sold, then;
b = a - 76 ...................... 2
Substitute equation 2 into 1
a + (a-76) = 438
a + a - 76 = 438
2a = 438 + 76
2a = 514
a = 514/2
a = 257 biology textbooks
From equation 2;
b = a - 76
b = 257 - 76
b = 181 psychology textbooks
Number of biology textbooks sold: 257 textbooks
Number of psychology textbooks sold: 181 textbooks
Answer:
y=2x+3
Step-by-step explanation:
Y is the total amount that the family pays. 2x represents 2 dollars for every person (so, 2 multiplied by the number of people). Finally, 3 represents the initial amount that they must pay, no matter how many are in the car.
Answer:
6 1/4
Step-by-step explanation:
Total length of the ribbon= 15 3/4 m= 63/4 m
One piece= 9 1/2 m= 19/2 m
Other piece length =X
X= 63/4-19/2
=63/4-38/4
=25/4
=6 1/4
Answer:
160
Step-by-step explanation:
(2.5 x 2)+(1.5 x 2) =8 (perimeter of scale)
8x20 = 160
