I=PRT/100
1. Make R (rate) subject
R/100= I/PT
2. Substitute and calculate
r/100= i/pt
r/100= 40/400 × 1
(<em>4</em><em>0</em><em> </em><em>i</em><em>s</em><em> </em>from 440-400.<em>T</em><em>h</em><em>e</em><em> </em><em>i</em><em>n</em><em>t</em><em>e</em><em>r</em><em>e</em><em>s</em><em>t</em>)
r/100= 0.1
r/100×100= 0.1×100
r=10% (interest rate per year)
To confirm
I=PRT
I= 400×10/100×1
I= $40 (Interest)
We need Pythagoras theorem here
a^2+b^2 = c^2
a, b = legs of a right-triangle
c = length of hypotenuse
Let S=shorter leg, in cm, then longer leg=S+2 cm
use Pythagoras theorem
S^2+(S+2)^2 = (10 cm)^2
expand (S+2)^2
S^2 + S^2+4S+4 = 100 cm^2 [collect terms and isolate]
2S^2+4S = 100-4 = 96 cm^2
simplify and form standard form of quadratic
S^2+2S-48=0
Solve by factoring
(S+8)(S-6) = 0 means (S+8)=0, S=-8
or (S-6)=0, S=6
Reject nengative root, so
Shorter leg = 6 cm
Longer leg = 6+2 cm = 8 cm
Hypotenuse (given) = 10 cm
Answer:
all work is shown and pictured
7/8 * cm/ month * 5 months =
35/8 cm
4 3/8 cm
Answer: 4 3/8 cm
