Jina wants to measure the width of a river. She marks off two right triangles, as shown in the figure. The base of the larger triangle has a length of 56m, and the base of the smaller triangle has a length of 26m. The height of the smaller triangle is 20.9m. How wide is the river? Round your answer to the nearest meter.

width of a river = 45m

Step-by-step explanation:

ration and proportion

let x = width of a river

x            20.9 m

 =    

56 m       26 m

x = (20.9 * 56) / 26

x = 45 m

therefore the width of a river is 45 m

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560