Work out the value of each expression, when r= 2.5 and t = 6. a) 4 (t - r)
b) 4t - r
c) 2(3t - 10)
d) (t - 2) ²
e) t
- + 4r - 3
3
f) 6r+t
——
3

a)  4(t - r) = 4(6 - 2.5) = 4 x 3.5 = 14

b)  4t - r = (4 x 6) - 2.5 = 24 - 2.5 = 21.5

c)  2(3t - 10) = 2(3 x 6 - 10) = 2(18 - 10) = 2 x 8 = 16

d)  (t - 2)² = (6 - 2)² = 4² = 4 x 4 = 16

e) cannot decipher the equation

f)  6r + t = 6 x 2.5 + 6 = 15 + 6 = 21

the circumference of wheel is 880cm calculate the diameter