Step-by-step explanation:
10/20 per try, .2multiply by 100 tries = 20
<h3>a)
![\frac{2}{5} \div ( - \frac{3}{4} )](https://tex.z-dn.net/?f=%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Cdiv%20%28%20%20-%20%5Cfrac%7B3%7D%7B4%7D%20%29)
</h3><h3>■Dividing a positive and a negative equals a negative: (+)÷(-)=(-)</h3>
<h2>
![- \frac{2}{5} \div \frac{3}{4}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Cdiv%20%20%5Cfrac%7B3%7D%7B4%7D%20)
</h2><h3>■To divide by a fraction, multiply by the reciprocal of that fraction</h3>
<h2>
![- \frac{2}{5} \times \frac{4}{3}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Ctimes%20%20%5Cfrac%7B4%7D%7B3%7D%20)
</h2><h3>■Multiply the fractions</h3>
<h2>
![- \frac{8}{15}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B8%7D%7B15%7D%20)
</h2>
<h3>Hence, Quotient =
![- \frac{8}{15}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B8%7D%7B15%7D%20)
</h3>
<h3>b)
![0.4 \div ( - 0.75)](https://tex.z-dn.net/?f=0.4%20%5Cdiv%20%20%28%20-%200.75%29)
</h3><h3>■Convert the decimals into a fractions</h3>
<h2>
![\frac{2}{5} \div ( - \frac{3}{4} )](https://tex.z-dn.net/?f=%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Cdiv%20%28%20-%20%20%5Cfrac%7B3%7D%7B4%7D%20%29)
</h2><h3>■Dividing a positive and a negative equals a negative: (+)÷(-)=(-)</h3>
<h2>
![- \frac{2}{5} \div \frac{3}{4}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Cdiv%20%20%5Cfrac%7B3%7D%7B4%7D%20)
</h2><h3>■To divide by a fraction, multiply by the reciprocal of that fraction</h3>
<h2>
![- \frac{2}{5} \times \frac{4}{3}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Ctimes%20%20%5Cfrac%7B4%7D%7B3%7D%20)
</h2><h3>■Multiply the fractions</h3>
<h2>
![- \frac{8}{15}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B8%7D%7B15%7D%20)
</h2><h3>Hence, Quotient is
![- \frac{8}{15}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B8%7D%7B15%7D%20)
</h3>
<h3>c)
![- \frac{2}{5} \div \frac{3}{4}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Cdiv%20%20%5Cfrac%7B3%7D%7B4%7D%20)
</h3><h3>■To divide by a fraction, multiply by the reciprocal of that fraction</h3>
<h2>
![- \frac{2}{5} \times \frac{4}{3}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Ctimes%20%20%5Cfrac%7B4%7D%7B3%7D%20)
</h2><h3>■Multiply the fractions</h3>
<h2>
![- \frac{8}{15}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B8%7D%7B15%7D%20)
</h2><h3>Hence, The Quotient is
![- \frac{8}{15}](https://tex.z-dn.net/?f=%20-%20%20%5Cfrac%7B8%7D%7B15%7D%20)
</h3>
Answer:
17b
Step-by-step explanation:
8980
80987
78987=
Let
x-----------> <span>uniform width surrounding the picture
we know that
(10+2x)*(12+2x)=224-----> 120+20x+24x+4x</span>²=224
4x²+44x+120-224=0
4x²+44x-104=0
using a graph tool-----> to resolve the second order equation
see the attached figure
the solution is
x=2 in
the answer is2 inches