Answer:
Option C. 140
Step-by-step explanation:
Base of a pyramid which has four triangular sides is four sided.
If pyramid contains seven layers of oranges then the layer at the bottom will have 7 oranges.
Since base is a square then other side of the square base will have the same number of oranges = 7.
Therefore number of oranges at the first layer will be = 7×7
Similarly other layers above this layer will have the same sequence
6×6, 5×5, 4×4, 3×3, 2×2, 1×1
Therefore total number of oranges = 7×7 + 6×6 + 5×5 + 4×4 + 3×3 + 2×2 + 1×1 = 49 + 36 + 25 + 16 + 9 + 4 + 1 = 140
Option C. 140 is the answer.
A grocer stacks oranges in a four-sided pyramid that is 7 layers high. Many oranges are in the pile are C.140
The orange is the fruit of the citrus species Citrus and sinensis in the family Rutaceae, native to China. Orange is also called sweet orange, to distinguish it from the related Citrus and aurantium, referred to as bitter orange.
The proper name of four-sided pyramid is a "tetrahedron". The tetrahedron has the extra interesting property of having all four triangular sides congruent
1st Layer: The 1st layer contains only 1 orange so it has only 1 orange
2nd layer: The 2nd layer has total 4 oranges. Calculation: [tex]2*2=4[/tex]
3rd layer: The 3rd layer has total 9 oranges. Calculation: [tex]3 * 3 = 9[/tex]
4th Layer: The 4th layer has total 16 oranges. Calculation: [tex]4 * 4 = 16[/tex].
5th layer: The 5th layer has total 25 oranges. Calculation: [tex]5 * 5 = 25[/tex]
6th layer: The 6th layer has total 36 oranges. Calculation: [tex]6 * 6 = 36[/tex]
7th layer: The 7th layer has total 49 oranges. Calculation: [tex]7 * 7 = 49[/tex].
Sum of all layers:
[tex]1+4+9+16+25+36+49 = 140[/tex]
Grade: 9
Subject: mathematics
Chapter: pyramid
Keywords: oranges, pyramid, four-sided, layers, pile
