Exercise 50

In 1936, John said to Bob, “You are twice my age”. If both were alive by the year 2000 and their ages added up to 140 years, how old was John in 2000? 68 80 74 72 76 Try to solve it before checking the answer. Answer 68 Step by Step Solution Between 1936 to […]

Exercise 49

You have a weighing scale and four weight plates of 1 kg, 2 kg, 4 kg, and 8 kg. Of the following weight measurements, which one cannot be obtained using the four given weight plates? 7 12 13 16 11 Try to solve it before checking the answer. Answer 16 Step by Step Solution Indeed, […]

Exercise 48

Given the sequence: ( 3, , 12, , 48, , 192, , ldots ); If ( n = 0, , 1, , 2, , 3, ldots ), then an expression describing the sequence is: ( 3 cdot 4^{n – 1} ) ( 3 n ) ( 3 cdot 4^n ) ( 4 n ) ( […]

Exercise 47

There are red, yellow, and blue balls in a bag. The number of blue balls is half the number of red balls, and there are twice as many yellow balls as red balls. If there are 25 balls among the yellow and blue balls, then the number of blue balls is: 10 15 4 5 […]

Exercise 46

In the illustration, the sum of angles ( angle AOB ) and ( angle COD ) is ( 55^{circ} ), and the sum of angles ( angle BOD ) and ( angle AOC ) is ( 95^{circ} ). What is the measure of angle ( angle AOD )? (55^{circ} ) (65^{circ} ) (75^{circ} ) (85^{circ} […]

Exercise 45

In the triangle ( triangle ABC ) we have that ( overline{AB} = 6 , cm ), ( overline{DC} = 2 sqrt{5} , cm ), and ( overline{DB} = 2 , cm ). Therefore, the area of the triangle ( triangle ABC ) is: ( 2 ; cm^2 ) ( 4 sqrt{5 – 1} ; […]

Exercise 44

Solving the equation: ( sqrt{ 5 (x + 33) } = x + 3 ), yields the following solution set: ( { 12, , 13 } ) ( { -12, , 13 } ) ( { 12, -13 } ) ( { -12, -13 } ) ( { 12 } ) Try to solve it […]

Exercise 43

If ( x = (-2, -2) ), ( y = (-1, , 3) ) and we know that ( -vec{x} + 2 vec{y} + 3 vec{z} = (6, , 5) ), then, necessarily, ( vec{z} ) is equal to: ( (-6, , 3) ) ( (2, -1) ) ( left( frac{2}{3}, , 1 right) ) […]

Exercise 42

The expression ( cfrac{x – 5}{sqrt{x – 5}} ) equals: ( 1 ) ( cfrac{ sqrt{ (x – 5)^3 } }{x – 5} ) ( cfrac{2x}{x – 5} ) ( cfrac{x + 5}{x – 5} ) ( cfrac{x^2 – 25}{x – 5} ) Try to solve it before checking the answer. Answer ( cfrac{ sqrt{ […]

Exercise 41

If 17 is added to a number, then 5 is subtracted from the sum, and the resulting difference is multiplied by 4, the result is 132. What was the original number? 10 12 19 21 31 Try to solve it before checking the answer. Answer 21 Step by Step Solution If (x) is the original […]